💻

Computer Applications — Class X

Master computer fundamentals, Python programming, databases, networking and HTML for CBSE board exams.

⚡ 5 Units🐍 Python Programs📝 Mock Exams🎯 Board Ready

Units

20+

MCQs

Exam Modes

100

Max Marks

🖥️

Computer Basics

Hardware, Software, OS

🐍

Python

Programs & Concepts

🗄️

Databases & SQL

MySQL Queries

🌐

Networking

Internet & Protocols

🏷️

HTML

Web Design Tags

Your Badges

💻 Computer Fundamentals

Computer Organisation · Input/Output · Memory · Software · Operating System · Cyber Safety

📖 Core Theory

Computer Organisation

A computer system consists of: Input Unit (keyboard, mouse, scanner), CPU (Control Unit + ALU + Registers), Memory (RAM, ROM), Output Unit (monitor, printer). CPU is the "brain" — executes instructions. ALU does arithmetic and logical operations. Control Unit coordinates all operations.

CPU Components

ALU (Arithmetic Logic Unit): performs +,-,×,÷ and comparisons. Control Unit: fetches, decodes, executes instructions. Registers: small, fast storage inside CPU (Accumulator, PC, IR, MAR, MDR).

RAM vs ROM

RAM (Random Access Memory): volatile, read-write, primary memory. ROM (Read Only Memory): non-volatile, permanently stores BIOS. Cache memory: fastest, between CPU and RAM.

Memory Units

1 Byte = 8 bits. 1 KB = 1024 Bytes. 1 MB = 1024 KB. 1 GB = 1024 MB. 1 TB = 1024 GB. ASCII: 8-bit code for characters. Unicode: 16-bit, multilingual.

Operating System

Software that manages hardware and provides user interface. Functions: process management, memory management, file management, I/O management. Examples: Windows, Linux, macOS, Android.

🔑 Key Facts — Computer Fundamentals

Binary: base 2 (0,1). Decimal to binary: divide repeatedly by 2, read remainders upwards.

Octal: base 8. Hexadecimal: base 16 (0-9, A-F where A=10...F=15).

1's complement: invert all bits. 2's complement: invert + add 1 (used for negative numbers).

Boolean: AND (A.B), OR (A+B), NOT (A'), NAND, NOR, XOR. De Morgan's: (A.B)' = A'+B'

✏️ Worked Examples

Example 1 — Number Systems (Board 2023, 2M)

Q: Convert (110101)2 to decimal.

Write positional values: 1×2^5 + 1×2^4 + 0×2^3 + 1×2^2 + 0×2^1 + 1×2^0

= 32 + 16 + 0 + 4 + 0 + 1 = 53

✅ (110101)2 = (53)10

📝 Practice Questions — Computer Fundamentals

MCQ 1 Which of the following is a secondary storage device?
(A) RAM (B) CPU (C) Hard Disk (D) Cache
Ans: (C) Hard Disk

MCQ 2 Convert (1010)₂ to decimal:
(A) 8 (B) 10 (C) 12 (D) 5
Ans: (B) 10 — 1×8+0×4+1×2+0×1 = 10

MCQ 3 Which Boolean law states: A + A' = 1?
(A) Absorption (B) Complement law (C) Identity (D) De Morgan's)
Ans: (B) Complement law

A-R A: Cache memory is faster than RAM.
R: Cache memory is built directly into or very close to the CPU and uses SRAM, which operates at processor speed — much faster than DRAM used in main RAM.
Ans: (A)

Case: Priya is learning about number systems. She encounters the binary number (11011001)₂ and wants to convert it to decimal, then find its 2's complement for signed representation.

Q1 (2M) Convert (11011001)₂ to decimal.
Ans: 128+64+0+16+8+0+0+1 = 217.

Q2 (2M) Find 2's complement of (11011001)₂.
Ans: 1's complement = 00100110. Add 1 = 00100111. So 2's complement = 00100111.

Q3 (1M) What does 2's complement represent?
Ans: 2's complement is used to represent negative numbers in binary — it allows subtraction to be performed using addition circuits.

SA (3M) Distinguish between RAM and ROM with any three points.
Ans: RAM (Random Access Memory): (1) Volatile — data lost when power is off. (2) Read-write memory — can be both read and modified. (3) Used for storing data and programs currently in use (primary/temporary memory). ROM (Read Only Memory): (1) Non-volatile — retains data even without power. (2) Read-only — cannot normally be written to during normal operation. (3) Used for storing BIOS and firmware — permanent instructions for booting the computer.

LA (5M) Explain the functions of an Operating System. Give two examples.
Ans: An Operating System (OS) is system software that acts as an interface between the user and the computer hardware. Functions: (1) Process Management: Manages running programs — scheduling CPU time, creating and terminating processes. (2) Memory Management: Allocates and deallocates memory to programs; manages virtual memory. (3) File Management: Organises files in directories, controls file access and security. (4) Device Management: Manages I/O devices through device drivers — keyboard, printer, monitor. (5) Security and Access Control: Protects the system through user authentication, passwords, and permissions. Examples: Windows 11 (Microsoft) and Ubuntu Linux (open-source). Both manage these five functions but with different interfaces and licensing models.

🐍 Python Programming

Data Types · Control Flow · Functions · Strings · Lists · Tuples · Dictionaries · File Handling

📖 Core Theory

Python Basics

Python is an interpreted, high-level, object-oriented language. Dynamically typed (no explicit type declaration). Indentation defines code blocks. Key data types: int, float, str, bool, list, tuple, dict, set. print() for output, input() for input (returns string).

List vs Tuple

List: mutable, ordered, allows duplicates. L=[1,2,3]. Tuple: immutable, ordered, allows duplicates. T=(1,2,3). Lists use square brackets, tuples use parentheses.

Dictionary

Key-value pairs. D = {'name': 'Ali', 'age': 15}. Keys must be unique and immutable. Access: D['name']. Methods: keys(), values(), items(), get(), update().

String Methods

s.upper(), s.lower(), s.strip(), s.split(), s.replace(old,new), s.find(sub), s.count(sub), s.startswith(), s.endswith(), len(s), s[i], s[i:j].

Control Flow

if-elif-else for conditions. for loop: iterates over sequence. while loop: runs while condition true. break: exit loop. continue: skip rest of loop body. range(start, stop, step).

🔑 Python Syntax Reference

Function: def myFunc(param): ... return value

File read: f = open("file.txt","r"); data = f.read(); f.close()

File write: f = open("file.txt","w"); f.write("hello"); f.close()

List ops: append(), insert(i,v), remove(v), pop(i), sort(), reverse(), len()

✏️ Worked Examples

Example 1 — Python Code (Board 2023, 3M)

Q: Write a Python program to find the largest of three numbers.

a = int(input("Enter first number: ")); b = int(input("Enter second: ")); c = int(input("Enter third: "))

if a >= b and a >= c: print("Largest:", a); elif b >= a and b >= c: print("Largest:", b); else: print("Largest:", c)

✅ Use nested if-elif-else comparing all three variables.

📝 Practice Questions — Python Programming

MCQ 1 What is the output of: print(type([1,2,3]))?
(A) <class 'tuple'> (B) <class 'list'> (C) <class 'dict'> (D) <class 'set'>
Ans: (B) <class 'list'>

MCQ 2 Which method adds an element at the END of a list?
(A) insert() (B) add() (C) append() (D) extend()
Ans: (C) append()

MCQ 3 What does s[2:5] return for s = "PYTHON"?
(A) "THO" (B) "YTH" (C) "HON" (D) "PYT"
Ans: (A) "THO" — index 2,3,4 → T,H,O

A-R A: Tuples are preferred over lists when data should not be changed.
R: Tuples are immutable — once created, elements cannot be modified, making them suitable for constant data like days of the week or fixed configurations.
Ans: (A)

Case: Consider the following Python code:
marks = {'Priya':85, 'Raj':92, 'Sam':78} for name in marks: if marks[name] >= 90: print(name, "gets A grade") else: print(name, "gets B grade")

Q1 (1M) What is the data type of 'marks'? Ans: Dictionary (dict).

Q2 (2M) What will be the output? Ans: Priya gets B grade. Raj gets A grade. Sam gets B grade.

Q3 (2M) Modify the code to also print the marks along with grade.
Ans: Change print statements: print(name, marks[name], "gets A grade") and print(name, marks[name], "gets B grade").

SA (3M) What is the difference between a list and a dictionary in Python? Give one example of each.
Ans: A list is an ordered, mutable collection that stores elements accessed by index (position). Example: fruits = ['apple','banana','mango']; fruits[0] gives 'apple'. A dictionary is an unordered (Python 3.7+ maintains insertion order), mutable collection that stores key-value pairs. Elements are accessed by key, not position. Example: student = {'name':'Priya','age':15}; student['name'] gives 'Priya'. Lists are used when order matters; dictionaries when named access to data (like a database record) is needed.

LA (5M) Write a Python program that reads 10 numbers from the user, stores them in a list, and then prints: (a) all even numbers, (b) the sum, (c) the largest number.
Ans:

nums = []
for i in range(10):
    nums.append(int(input(f"Enter number {i+1}: ")))

print("Even numbers:", [x for x in nums if x%2==0])
print("Sum:", sum(nums))
print("Largest:", max(nums))

The program uses a loop to fill the list, list comprehension to filter evens, and built-in functions sum() and max().

🗄️ Database Management (SQL)

RDBMS Concepts · SQL Commands · DDL · DML · Queries · Aggregate Functions

📖 Core Theory

RDBMS and SQL

RDBMS: data stored in tables (rows and columns). Table = Relation; Row = Tuple/Record; Column = Attribute/Field. Key concepts: Primary Key (unique, not null), Foreign Key (links to another table). SQL = Structured Query Language.

DDL vs DML

DDL (Data Definition Language): CREATE TABLE, ALTER TABLE, DROP TABLE. DML (Data Manipulation Language): INSERT, UPDATE, DELETE, SELECT. These are the two categories of SQL commands.

SELECT Syntax

SELECT col1, col2 FROM tablename WHERE condition ORDER BY col ASC/DESC; * selects all columns. WHERE filters rows. ORDER BY sorts results.

Aggregate Functions

COUNT(*): counts rows. SUM(col): sum of values. AVG(col): average. MAX(col): maximum. MIN(col): minimum. Used with GROUP BY to summarise groups.

Joins (Basic)

Cartesian Product: SELECT * FROM T1, T2 — all combinations. Equijoin: SELECT * FROM T1, T2 WHERE T1.key = T2.key — matching rows only.

🔑 SQL Quick Reference

CREATE TABLE Student(RollNo INT PRIMARY KEY, Name VARCHAR(30), Marks INT);

INSERT INTO Student VALUES(1, 'Ali', 95);

SELECT Name, Marks FROM Student WHERE Marks > 80 ORDER BY Marks DESC;

UPDATE Student SET Marks=98 WHERE RollNo=1;

✏️ Worked Examples

Example 1 — SQL Query (Board 2023, 3M)

Q: Table: Employee(EmpID, Name, Dept, Salary). Write SQL to: (a) Show all employees in 'HR'; (b) Find average salary; (c) Show names in alphabetical order.

(a) SELECT * FROM Employee WHERE Dept='HR';

(b) SELECT AVG(Salary) FROM Employee;

✅ WHERE for filtering, AVG() for aggregation, ORDER BY ASC for alphabetical.

📝 Practice Questions — SQL & Database

MCQ 1 Which SQL command is used to delete an entire table's data but keep the structure?
(A) DELETE (B) DROP (C) TRUNCATE (D) REMOVE)
Ans: (A) DELETE (without WHERE) or TRUNCATE — TRUNCATE specifically removes all rows. DROP removes the table itself.

MCQ 2 To find the number of records in a table, use:
(A) SUM(*) (B) COUNT(*) (C) TOTAL(*) (D) NUMBER()
Ans: (B) COUNT(*)

MCQ 3 Which clause is used to filter grouped results in SQL?
(A) WHERE (B) HAVING (C) GROUP BY (D) ORDER BY)
Ans: (B) HAVING — WHERE filters rows; HAVING filters groups.

A-R A: A Primary Key cannot contain NULL values.
R: A Primary Key uniquely identifies each record in a table. If it could be NULL, records could not be uniquely identified, violating the fundamental purpose of the key.
Ans: (A)

Case: Consider a table STUDENT(SNo, SName, Class, Marks, City). Answer the following SQL queries:

Q1 (1M) Display names of all students from Delhi.
Ans: SELECT SName FROM STUDENT WHERE City='Delhi';

Q2 (1M) Display highest marks in each class.
Ans: SELECT Class, MAX(Marks) FROM STUDENT GROUP BY Class;

Q3 (2M) Display SName and Marks of students whose marks are between 80 and 95, ordered by marks descending.
Ans: SELECT SName, Marks FROM STUDENT WHERE Marks BETWEEN 80 AND 95 ORDER BY Marks DESC;

Q4 (1M) Count total number of students in Class 10.
Ans: SELECT COUNT(*) FROM STUDENT WHERE Class=10;

SA (3M) Distinguish between DDL and DML in SQL with two examples each.
Ans: DDL (Data Definition Language) deals with the structure (schema) of the database. It creates, modifies, and deletes database objects. Examples: (1) CREATE TABLE Student (...) — creates a new table. (2) DROP TABLE Student — deletes the table and all its data. DML (Data Manipulation Language) deals with the data within the database. It inserts, updates, deletes and retrieves records. Examples: (1) INSERT INTO Student VALUES (1,'Ali','X',92,'Delhi') — adds a record. (2) UPDATE Student SET Marks=95 WHERE SNo=1 — updates a record.

🌐 Networking and Cyber Safety

Types of Networks · Protocols · Internet · Cyber Crime · Cyber Ethics

📖 Core Theory

LAN vs WAN

LAN (Local Area Network): small area (building, campus). MAN (Metropolitan): city-wide. WAN (Wide Area Network): large geographic area — the Internet is the largest WAN.

Protocols

HTTP: web pages. HTTPS: secure web. FTP: file transfer. SMTP: email sending. POP3/IMAP: email receiving. TCP/IP: fundamental internet protocol suite.

IP Address

Unique 32-bit address for each device on internet (IPv4: e.g., 192.168.1.1). DNS translates domain names (www.google.com) to IP addresses. MAC address: physical address of network card.

Cyber Threats

Malware (virus, worm, trojan, ransomware). Phishing (fake emails/sites to steal data). Hacking. Cyberbullying. Identity theft. Spam. Prevention: antivirus, strong passwords, 2FA, SSL.

🔑 Networking Quick Facts

Transmission media: twisted pair (telephone), coaxial cable, optical fibre (fastest, least interference)

Topology: Bus, Star, Ring, Mesh, Tree. Star most common in LANs (easy to manage)

Bandwidth: max data transmitted per second. Mbps = megabits per second.

Cyber ethics: do not copy software illegally; protect personal data; respect others online

✏️ Worked Examples

Example 1 — Networking (Board 2022, 3M)

Q: What is the difference between client-server and peer-to-peer networks?

Client-Server: dedicated server provides services (files, email, web) to clients. Centralised, more secure, expensive. Used in offices, banks.

Peer-to-Peer (P2P): all computers equal, share resources directly. No dedicated server. Less expensive, less secure. Home networks, file sharing.

✅ Client-Server: centralised, dedicated server. P2P: decentralised, all nodes equal.

📝 Practice Questions — Networking & Cyber Safety

MCQ 1 Which network topology connects all devices to a single central hub?
(A) Ring (B) Bus (C) Star (D) Mesh)
Ans: (C) Star

MCQ 2 What does IP stand for?
(A) Internet Protocol (B) Internal Protocol (C) Input Processing (D) Integrated Protocol)
Ans: (A) Internet Protocol

MCQ 3 Which of the following is NOT a cybersecurity threat?
(A) Phishing (B) Ransomware (C) Firewall (D) Malware)
Ans: (C) Firewall — a firewall is a security tool, not a threat.

A-R A: Https is more secure than http.
R: HTTPS uses SSL/TLS encryption to secure data transfer between browser and server, preventing eavesdropping and tampering — unlike HTTP which transmits data in plaintext.
Ans: (A)

Case: A school is setting up a computer lab with 30 computers. The network administrator must choose a topology, assign IP addresses, and set up internet access. She also needs to protect the network from cyber threats.

Q1 (1M) Which topology is best for this lab and why?
Ans: Star topology — easy to manage, failure of one node does not affect others, easy to add new computers.

Q2 (1M) What does an IP address identify?
Ans: Each device on a network — it uniquely identifies a computer on a network (like a postal address).

Q3 (2M) Name two cyber threats and their prevention.
Ans: (1) Phishing — fraudulent emails that steal credentials; prevented by not clicking unknown links and using email filters. (2) Malware — malicious software; prevented by antivirus software and regular updates.

SA (3M) What is a Firewall? State its two uses.
Ans: A Firewall is a network security system — hardware or software — that monitors and controls incoming and outgoing network traffic based on predefined security rules. It acts as a barrier between a trusted internal network and untrusted external networks (like the internet). Uses: (1) Packet Filtering — examines each data packet and blocks those that don't meet the security criteria (e.g., packets from unauthorised IP addresses). (2) Application-level Control — blocks access to specific websites or services (e.g., blocking social media sites in an office). Without a firewall, the network is vulnerable to unauthorised access, hacking, and data theft.

🌐 HTML and Web Development

HTML Tags · Tables · Forms · CSS Basics · Javascript Basics

📖 Core Theory

HTML Structure

html → head → (title, style, meta) + body → (all visible content). Tags: opening tag + content + closing tag. Self-closing: br, img, hr, input.

Text Formatting

h1-h6 (headings), p (paragraph), b/strong (bold), i/em (italic), u (underline), sup (superscript), sub (subscript), br (line break), hr (horizontal rule).

Tables

table → tr (row) → th (header cell) or td (data cell). Attributes: border, width, cellpadding, cellspacing, colspan, rowspan, align.

Forms

form → input (text, password, radio, checkbox, submit, reset), select (dropdown) + option, textarea. Attributes: action, method (GET/POST), name, value.

🔑 HTML Reference

Link: a href="url" target="_blank" — opens in new tab

Image: img src="pic.jpg" alt="desc" width="200" height="150"

Table cell spanning: td colspan="2" — spans 2 columns; rowspan="2" — spans 2 rows

CSS inline: style="color:red; font-size:16px; background-color:yellow"

✏️ Worked Examples

Example 1 — HTML Table (Board 2023, 4M)

Q: Write HTML code to create a table with 2 rows and 3 columns with heading row.

<tr><td>Ali</td><td>15</td><td>Delhi</td></tr>

<tr><td>Priya</td><td>16</td><td>Mumbai</td></tr></table>

✅ table with border, th for headings, td for data, one tr per row.

📝 Practice Questions — HTML & Web Development

MCQ 1 Which HTML tag creates a hyperlink?
(A) <link> (B) <a> (C) <href> (D) <nav>)
Ans: (B) <a>

MCQ 2 Which CSS property changes text colour?
(A) font-color (B) text-color (C) color (D) background-color)
Ans: (C) color

MCQ 3 What does HTML stand for?
(A) Hypertext Markup Language (B) High Text Machine Language (C) Hyper Transfer Markup Link (D) Hyperlink Text Model Language)
Ans: (A) Hypertext Markup Language

A-R A: The <table> tag in HTML requires <tr>, <th>, and <td> tags inside it.
R: <tr> defines a row, <th> defines a header cell, and <td> defines a data cell — all three are required to form a valid and structured HTML table.
Ans: (A)

Case: Rahul wants to create a simple web page about his school. The page should have a heading "Welcome to Our School", a paragraph describing the school, an ordered list of subjects offered, and a link to the school's website (http://myschool.com).

Q1 (1M) Which tag makes the main heading? Ans: <h1>Welcome to Our School</h1>

Q2 (1M) Which tag creates an ordered list? Ans: <ol> with <li> items inside.

Q3 (3M) Write the complete HTML code for this page.
Ans:
<!DOCTYPE html>
<html>
<head><title>My School</title></head>
<body>
<h1>Welcome to Our School</h1>
<p>Our school was founded in 1990 and offers quality education.</p>
<ol><li>Mathematics</li><li>Science</li><li>English</li></ol>
<a href="http://myschool.com">Visit our website</a>
</body>
</html>

SA (3M) What is the difference between <ol> and <ul> in HTML? Give the code for each.
Ans: <ol> (Ordered List) displays items with numbers or letters — useful for steps or ranked items. <ul> (Unordered List) displays items with bullet points — useful for collections without a specific order. Code: <ol><li>Step 1</li><li>Step 2</li></ol> produces 1. Step 1, 2. Step 2. <ul><li>Apple</li><li>Mango</li></ul> produces • Apple, • Mango.

📝 Practice Paper — Comp App

Board-Pattern Questions

📖 Important Questions

Problem — Python (Board 2022, 5M)

Q: Write a Python function that accepts a list and returns sum and average of its elements.

def calcStats(lst): total = sum(lst); avg = total / len(lst); return total, avg

nums = [10, 20, 30, 40, 50]; s, a = calcStats(nums); print("Sum:", s, "Average:", a)

Output: Sum: 150, Average: 30.0. Python's built-in sum() and len() make this concise.

✅ Function uses sum() and len() to compute total and average, returned as a tuple.

🏠 Computer Applications X — Home

CBSE Class X · Computer Applications (Code 165) · Full Study Portal

📚 What You'll Master

💻 Computing Basics
History, types of computers, I/O devices, memory hierarchy

🐍 Python Programming
Data types, control flow, functions, file handling, libraries

🗄️ Databases & SQL
RDBMS concepts, SQL queries — SELECT, INSERT, UPDATE, DELETE

🌐 HTML & CSS
Web page structure, tags, styling, forms, tables

📶 Networking
Network types, protocols, IP, cyber security basics

🏆 Board Weightage
Python: 35M | SQL: 20M | HTML: 15M | Networking: 10M

💻 Computer Fundamentals

Unit 1 · Hardware · Software · Memory · I/O Devices

📖 Core Theory

Computer
Electronic device that processes data according to instructions (programs)

Hardware
Physical components: CPU, RAM, HDD, keyboard, monitor

Software
Programs: System software (OS, drivers) + Application software

CPU Components
ALU (arithmetic), CU (control), Registers (temporary storage)

Primary Memory
RAM (volatile, fast, temporary) | ROM (non-volatile, permanent)

Secondary Memory
HDD, SSD, CD/DVD, Pen drive — permanent storage

✏️ Worked Examples

Convert 45 (decimal) to Binary (Board 2023, 2M)

45÷2=22 r1 | 22÷2=11 r0 | 11÷2=5 r1 | 5÷2=2 r1 | 2÷2=1 r0 | 1÷2=0 r1

Read remainders bottom-up: 101101

✅ 45 (decimal) = 101101 (binary)

Convert 11011 (binary) to Decimal (Board 2024, 2M)

1×2⁴ + 1×2³ + 0×2² + 1×2¹ + 1×2⁰ = 16+8+0+2+1 = 27

✅ 11011 (binary) = 27 (decimal)

⚡ Quick Activity

Difference between RAM and ROM?

RAM: volatile, read-write, used for running programs. ROM: non-volatile, read-only, stores BIOS/firmware. RAM loses data on power off; ROM retains it.

🐍 Python Programming

Unit 2 · Variables · Control Flow · Functions · File Handling

📖 Core Theory

Data Types
int, float, str, bool, list, tuple, dict, set

Operators
+,-,*,/,//,%,** | ==,!=,>,< | and,or,not

if-elif-else
Conditional execution based on boolean

Loops
for (iterate sequence) | while (condition-based)

Functions
def name(params): body | return value

Lists
Mutable ordered sequence. append(), remove(), sort()

String methods: upper(), lower(), strip(), split(), replace(), len()
List ops: append(x), insert(i,x), pop(i), sort(), reverse(), len()
File handling: open(file,mode) — 'r','w','a','rb'. read(), write(), close()
Exception handling: try: ... except ExceptionType: ... finally: ...
Libraries: import math | math.sqrt(), math.pow() | import random | random.random()

✏️ Worked Examples

Python program — Sum of digits of a number (Board 2024, 3M)

Code

n = int(input("Enter number: "))
s = 0
while n > 0:
    s += n % 10
    n //= 10
print("Sum of digits:", s)

✅ For n=123: s=1+2+3=6

Python — Check prime number (Board 2023, 3M)

Code

n = int(input("Enter: "))
if n < 2:
    print("Not prime")
else:
    prime = True
    for i in range(2, int(n**0.5)+1):
        if n % i == 0:
            prime = False; break
    print("Prime" if prime else "Not prime")

✅ Standard prime check

File handling — Read and display contents (Board 2024, 2M)

Code

f = open("data.txt", "r")
content = f.read()
print(content)
f.close()

✅ Always close file or use with open() as f:

⚡ Quick Activity

Output of: print(type(3.14)) and print(type("hello"))

What is the output: lst=[1,2,3]; lst.append(4); print(lst[-1])?

4 (last element after append)

🗄️ SQL & Databases

Unit 3 · RDBMS Concepts · SQL Commands · Queries

📖 Core Theory

DBMS
Software to create, manage, access databases efficiently

Table/Relation
Rows (records/tuples) × Columns (fields/attributes)

Primary Key
Unique identifier for each row; cannot be NULL

Foreign Key
Attribute referencing primary key of another table

DDL
CREATE, DROP, ALTER (structure definition)

DML
INSERT, UPDATE, DELETE (data manipulation)

SELECT syntax:
SELECT col1, col2 FROM table WHERE condition ORDER BY col [ASC|DESC];

Aggregate functions: COUNT(), SUM(), AVG(), MAX(), MIN()
GROUP BY + HAVING: GROUP BY col HAVING condition (filters groups)
JOIN: SELECT * FROM t1, t2 WHERE t1.id = t2.id; (Cartesian join with condition)

✏️ Worked Examples

Table: STUDENT(RollNo, Name, Class, Marks) — Write queries (Board 2024, 4M)

Display all students from Class 10:
SELECT * FROM STUDENT WHERE Class='10';

Display names with marks > 90:
SELECT Name FROM STUDENT WHERE Marks > 90;

iii

Count students in each class:
SELECT Class, COUNT(*) FROM STUDENT GROUP BY Class;

Average marks of all students:
SELECT AVG(Marks) FROM STUDENT;

✅ All 4 queries correct

⚡ Quick Activity

Difference between DELETE and DROP?

DELETE: DML command, removes rows (data), table structure remains. DROP: DDL command, removes entire table including structure and data. DELETE can have WHERE; DROP cannot.

🌐 HTML & CSS

Unit 4 · Web Design · HTML Tags · CSS Styling · Forms

📖 Core Theory

HTML
HyperText Markup Language — structure of web pages

Tags
<html><head><body><p><h1..6><a><img><table><form>

Attributes
href, src, width, height, border, class, id, name

CSS
Cascading Style Sheets — presentation/styling

CSS Selectors
Element (p), Class (.class), ID (#id)

Box Model
content → padding → border → margin

Basic page structure:
<!DOCTYPE html> <html> <head><title>...</title></head> <body>...</body> </html>

Hyperlink: <a href="url">text</a>
Image: <img src="file.jpg" width="300" height="200">
Table: <table><tr><th>header</th><td>data</td></tr></table>
Form: <form action="submit.php" method="GET"><input type="text" name="nm"></form>

✏️ Worked Examples

Create HTML page with table of 3 subjects, marks, grade (Board 2023, 4M)

Code

<table border="1">
  <tr><th>Subject</th><th>Marks</th><th>Grade</th></tr>
  <tr><td>Maths</td><td>92</td><td>A1</td></tr>
  <tr><td>Science</td><td>88</td><td>A2</td></tr>
  <tr><td>English</td><td>85</td><td>B1</td></tr>
</table>

✅ Table with headers, 3 data rows

⚡ Quick Activity

Difference between <b> and <strong>?

<b> makes text bold (purely visual). <strong> makes text bold AND marks it as semantically important (used by screen readers). Prefer <strong> for meaningful emphasis.

📶 Networking & Cyber Safety

Unit 5 · Network Types · Protocols · Internet · Cyber Security

📖 Core Theory

LAN
Local Area Network — small area (building/campus)

MAN
Metropolitan Area Network — city-wide

WAN
Wide Area Network — countries/continents (Internet)

Topology
Star (hub-based) | Bus (single cable) | Ring | Mesh

Protocols
HTTP/HTTPS, FTP, SMTP, POP3, TCP/IP, DNS

IP Address
Unique 32-bit identifier for each device (IPv4: a.b.c.d)

Network devices:
Hub: broadcasts to all | Switch: sends to specific MAC | Router: connects networks | Modem: converts digital↔analog

Internet services: WWW, Email, FTP, Video conferencing, E-commerce, Social media
Cyber threats: Virus, Worm, Trojan, Phishing, Hacking, Identity theft
Safety tips: Strong passwords, HTTPS, Updates, Antivirus, Backup data

✏️ Worked Examples

Compare LAN, MAN, WAN (Board 2024, 3M)

LAN

Area: Building. Speed: High (1Gbps). Cost: Low. Example: School network

MAN

Area: City. Speed: Medium. Cost: Medium. Example: Cable TV network

WAN

Area: Global. Speed: Variable. Cost: High. Example: Internet

✅ Compare on: area, speed, cost, example

⚡ Quick Activity

What is the role of DNS?

Domain Name System — converts human-readable domain names (www.google.com) to IP addresses (142.250.x.x) that computers use. Like a phone book for the internet.

✏️ Worked Examples — All Units

Comprehensive Board-Pattern Problems with Step-by-Step Solutions

🐍 Python Advanced Programs

Fibonacci series up to n terms (Board 2023, 3M)

Code

n = int(input("Terms: "))
a, b = 0, 1
for i in range(n):
    print(a, end=" ")
    a, b = b, a+b

✅ Output for n=6: 0 1 1 2 3 5

Read list and find second largest (Board 2024, 4M)

Code

lst = [int(x) for x in input().split()]
lst.sort()
print("2nd largest:", lst[-2])

✅ sort() then access [-2]

🗄️ SQL Advanced Queries

Table EMPLOYEE(EmpID,Name,Dept,Salary). Complex queries (Board 2024, 5M)

Max salary in each department:
SELECT Dept, MAX(Salary) FROM EMPLOYEE GROUP BY Dept;

Names with salary between 50000-80000:
SELECT Name FROM EMPLOYEE WHERE Salary BETWEEN 50000 AND 80000;

iii

Delete employee EmpID=5:
DELETE FROM EMPLOYEE WHERE EmpID=5;

Add column Phone to table:
ALTER TABLE EMPLOYEE ADD Phone VARCHAR(15);

✅ All 4 queries demonstrated

📝 Practice Papers

2 Full CBSE-Pattern Papers · Python + SQL + HTML + Networking

📄 Practice Paper 1 — Full Length (50 Marks)

Time: 2 Hours | Max Marks: 50 | Class X Computer Applications

Section A — MCQ (10 × 1 = 10 Marks)

Which of the following is NOT an input device? (a) Keyboard (b) Scanner (c) Printer (d) Mouse [1M]
Ans: (c) Printer is output device

1 GB = ? (a) 1000 MB (b) 1024 KB (c) 1024 MB (d) 1000 KB [1M]
Ans: (c)

Output of print(type(42)): (a) int (b) <class 'int'> (c) number (d) integer [1M]
Ans: (b)

Python operator for integer division: (a) / (b) // (c) % (d) ** [1M]
Ans: (b)

Which SQL command retrieves data? (a) INSERT (b) DELETE (c) SELECT (d) UPDATE [1M]
Ans: (c)

Primary key property: (a) Can be NULL (b) Must be unique (c) Can repeat (d) Optional [1M]
Ans: (b)

Which tag creates hyperlink? (a) <link> (b) <href> (c) <a> (d) <url> [1M]
Ans: (c)

LAN covers: (a) City (b) Country (c) Building/campus (d) Continent [1M]
Ans: (c)

DNS stands for: (a) Data Network System (b) Domain Name System (c) Direct Net Server (d) Digital Name Service [1M]
Ans: (b)

10.

Binary of 13: (a) 1011 (b) 1101 (c) 1001 (d) 1111 [1M]
Ans: (b) 8+4+0+1=13

Section B — Short Answer (5 × 2 = 10 Marks)

11.

Difference between RAM and ROM. [2M]
RAM: volatile, read-write, used while program runs. ROM: non-volatile, read-only, stores BIOS.

12.

What is a list in Python? Write code to create and display a list of 3 fruits. [2M]
List = ordered, mutable collection. fruits=["apple","mango","banana"]; print(fruits)

13.

Write SQL to: (i) Create table BOOK(BookID, Title, Price) (ii) Insert one record. [2M]
(i) CREATE TABLE BOOK(BookID INT PRIMARY KEY, Title VARCHAR(50), Price FLOAT);
(ii) INSERT INTO BOOK VALUES(1,'Python Guide',299);

14.

What is the purpose of <form> tag? Write syntax with method and action. [2M]
<form> collects user input and submits to server. <form action="submit.php" method="GET">...</form>

15.

Name two cyber threats and their prevention. [2M]
1. Phishing: Use HTTPS, verify sender. 2. Virus: Install antivirus, don't open unknown attachments.

Section C — Long Answer (3 × 5 = 15 Marks)

16.

Write Python program to: read 10 numbers from user, find count of even and odd numbers, display both counts. [5M]
even = odd = 0 for i in range(10): n = int(input(f"Enter number {i+1}: ")) if n % 2 == 0: even += 1 else: odd += 1 print("Even count:", even) print("Odd count:", odd)

17.

Table: STUDENT(SID,Name,Class,Marks,City). Write SQL for: (i) All from Delhi (ii) Names scoring >80 (iii) Average marks per city (iv) Update City to 'Mumbai' where SID=3 (v) Count students in each class. [5M]
(i)SELECT * FROM STUDENT WHERE City='Delhi';
(ii)SELECT Name FROM STUDENT WHERE Marks>80;
(iii)SELECT City,AVG(Marks) FROM STUDENT GROUP BY City;
(iv)UPDATE STUDENT SET City='Mumbai' WHERE SID=3;
(v)SELECT Class,COUNT(*) FROM STUDENT GROUP BY Class;

18.

Create HTML page with: (i) Page title "My School" (ii) Heading H1 (iii) Table of 3 teachers with Name, Subject, Experience (iv) Background color using CSS. [5M]
Student to write complete HTML page with all tags demonstrated in class.

Section D — Case-Based (3 × 5 = 15 Marks)

19.

Case — School Library System: A library database has TABLE BOOKS(BID,Title,Author,Genre,Available). (i) List all available books (Available='Yes') (ii) Find books by author 'R.K. Narayan' (iii) Count books per genre (iv) Delete books with BID=7. [5M]
(i)SELECT * FROM BOOKS WHERE Available='Yes';
(ii)SELECT * FROM BOOKS WHERE Author='R.K. Narayan';
(iii)SELECT Genre,COUNT(*) FROM BOOKS GROUP BY Genre;
(iv)DELETE FROM BOOKS WHERE BID=7;

20.

Case — Python Grade Calculator: Write Python program to: (i) Accept marks in 5 subjects (ii) Calculate total and percentage (iii) Assign grade (A:>90, B:>75, C:>60, D:pass). [5M]
subjects = ["Maths","Science","English","Hindi","SST"] total = 0 for s in subjects: m = int(input(f"{s} marks: ")) total += m pct = total / 5 if pct >= 90: grade = 'A' elif pct >= 75: grade = 'B' elif pct >= 60: grade = 'C' else: grade = 'D' print(f"Total: {total}, %: {pct}, Grade: {grade}")

21.

Case — Network Design: A company has 5 floors, 20 computers each. (i) Which network type? (ii) Best topology? (iii) What device connects floors? (iv) What protocol for internet browsing? (v) How to secure the network? [5M]
(i)LAN (ii)Star topology — easy troubleshooting (iii)Switch per floor, Router for internet (iv)HTTP/HTTPS (v)Firewall, passwords, HTTPS, antivirus

📄 Practice Paper 2 — Challenge Paper (50 Marks)

Higher difficulty · Board-exam style

Selected Challenging Problems

Python: List of words → display only words with length > 5. [3M]
words=[...]; [print(w) for w in words if len(w)>5]

SQL: EMPLOYEE(EID,Name,Dept,Salary). Find departments where average salary > 50000. [3M]
SELECT Dept, AVG(Salary) FROM EMPLOYEE GROUP BY Dept HAVING AVG(Salary)>50000;

HTML: Create form with name, email, password fields, submit button. [4M]
<form> with <input type="text">, <input type="email">, <input type="password">, <input type="submit">

Python: Open file "names.txt", read all lines, count lines containing "Kumar". [4M]
f=open("names.txt","r"); count=sum(1 for line in f if "Kumar" in line); f.close()

Difference between client-side and server-side scripting with examples. [3M]
Client-side: runs in browser (JS, HTML). Server-side: runs on server, sends result (PHP, Python Django).

Write Python recursive function for factorial. [3M]
def fact(n): return 1 if n<=1 else n*fact(n-1)

SQL: Create and populate PRODUCT(PID,Name,Category,Price,Stock). Then: show low-stock items (Stock<10), total value per category. [5M]
SELECT * FROM PRODUCT WHERE Stock<10;
SELECT Category, SUM(Price*Stock) FROM PRODUCT GROUP BY Category;

What are cookies in web? How are they different from sessions? [2M]
Cookies: small data stored in browser, persist across sessions. Sessions: server-side, temporary, more secure.

📄 Practice Paper 2 — Computer Applications X (50 Marks)

Time: 2 Hours | All sections compulsory

Section A — Objective (1M each)

1. Which of the following is a valid Python variable name? (a) 2name (b) _name (c) name-1 (d) class [Ans: b]

2. Output of: print(type(3.14)) is: (a) <class 'int'> (b) <class 'float'> (c) <class 'str'> (d) None [Ans: b]

3. A database is: (a) Collection of programs (b) Organised collection of data (c) Type of network (d) Hardware device [Ans: b]

4. Which SQL command retrieves all rows from table 'Student'? (a) FETCH * FROM Student (b) GET * FROM Student (c) SELECT * FROM Student (d) DISPLAY * FROM Student [Ans: c]

5. HTML stands for: (a) High-Text Markup Language (b) HyperText Markup Language (c) Hyper Tool Making Language (d) None [Ans: b]

6-10. Topics: loop output tracing, Boolean operators, internet protocol, SQL WHERE clause, CSS selector syntax. [5M]

Section B — Short Answer (2M each)

11. Write the output: x=10; y=3; print(x//y, x%y, x**y) [2M]
Ans: 3 1 1000

12. Differentiate between: break and continue statements in Python. [2M]

13. What is a Primary Key? Give example. [2M]

14. Write SQL to create table Employee(EmpID int, Name varchar(30), Salary decimal). [2M]

15. What is a URL? Give its components. [2M]

Section C — Long Answer (3-4M each)

16. Write a Python program to check if a number is prime. Test it with 29 and 15. [4M]

17. Create an HTML page with: heading, paragraph, table with 3 rows/3 cols, and a hyperlink. [4M]

18. Write SQL to: (a) Insert record into Student(SNo, Name, Marks) (b) Update marks where SNo=3 (c) Delete records where Marks < 35 (d) Select top 5 students by marks desc. [4M]

19. Explain E-Commerce. List 4 advantages and 2 disadvantages. Give 2 examples of e-commerce platforms. [3M]

📄 Practice Paper 3 — Challenge (50 Marks)

Time: 2 Hours | Higher-Order Thinking

Section A — MCQ (10M)

1-10. Tricky MCQs on: Python list slicing output, nested loop trace, SQL JOIN concept, DNS resolution steps, CSS box model order, HTML form attributes, database ACID properties, cyber security types, IP address classes, cloud computing service models (IaaS/PaaS/SaaS). [10M]

Section B — Short Answer (20M)

11. Trace the output step by step: [3M]
lst = [1,2,3,4,5]
for i in range(len(lst)):
if lst[i] % 2 == 0:
print(lst[i]*lst[i], end=' ')

12. Write a Python program using function to check if a string is a palindrome. [3M]

13. Given Student(SNo, Name, Class, Marks): Write SQL for: (a) All students in Class X with Marks>80 (b) Average marks by class (c) Count students per class (d) Names starting with 'A'. [4M]

14. What is the difference between: (a) HTTP and HTTPS (b) FTP and SFTP (c) LAN and WAN. [3M]

15. Explain: (a) Cookies in web browsers (b) Session management (c) Phishing attack — how to identify and prevent. [3M]

16. Write HTML+CSS to create a responsive navigation bar with 5 links. [4M]

Section C — Long Answer (20M)

17. A school library database has: Books(ISBN, Title, Author, Price) and Issue(IssueID, StudentID, ISBN, IssueDate, ReturnDate). Write SQL to: (i) List all unreturned books (ii) Most popular book (iii) Update price of a book (iv) Count books per author. [5M]

18. Write a complete Python program for a Student Report Card: input name and 5 subject marks, compute total, average, and grade (A+:90+, A:80+, B:70+, C:60+, D:50+, F:below50), display formatted report. [5M]

19. Design a complete HTML webpage for your school with: (a) Title and meta tags (b) Navigation menu (c) About Us section (d) Image with alt text (e) Contact form with name, email, message (f) Footer with copyright. [5M]

20. Cyber Ethics and Safety: (a) What is digital footprint? (b) Explain 5 types of cyber crimes with examples (c) Steps to create a strong password (d) What is two-factor authentication? (e) Explain safe online communication practices. [5M]

📊 My Dashboard

Track Your Progress · Computer Applications X

Dashboard features will show your topic progress, time spent, and mock test scores as you study.

📜 PYQ Bank — Computer Applications (Class 10)

CBSE board questions 2019–2024 — Python, SQL, HTML, Networking, Basics

⚠️ Official CBSE PYQs — topic-wise with model answer hints

Python — Functions (2022, 2023, 2024)

Q: Write a Python function findMax(lst) to return the largest number in a list without using max(). (3 marks)
Hint: Initialize max_val = lst[0]; loop and compare; return max_val. Common error: not handling empty list.

Python — String Operations (2021, 2022)

Q: Write a program to count vowels in a given string. (2 marks)
Model: count=0; for ch in s: if ch.lower() in 'aeiou': count+=1; print(count)
PYQ also asks: palindrome check, reverse a string, count words.

SQL — SELECT with WHERE (2020, 2021, 2023)

Q: Write SQL to display Name and Salary of employees where Dept='Sales' and Salary>30000. (2 marks)
Answer: SELECT Name, Salary FROM Employee WHERE Dept='Sales' AND Salary>30000;

SQL — GROUP BY / ORDER BY (2022, 2024)

Q: Display department-wise average salary in descending order. (2 marks)
Answer: SELECT Dept, AVG(Salary) FROM Employee GROUP BY Dept ORDER BY AVG(Salary) DESC;

HTML — Tags and Attributes (2019, 2020, 2021)

Q: Write HTML code to create a table with 2 rows and 3 columns with a border. (3 marks)
Hint: <table border="1"> → <tr> × 2 → <td> × 3 per row. Also asked: forms, hyperlinks, image tag.

Networking — Concepts (2020, 2022, 2024)

Q: Differentiate between LAN and WAN. Give one example each. (2 marks)
Answer: LAN — limited area (school lab, office); WAN — wide geographic area (Internet, BSNL). Also asked: IP address, MAC address, DNS, HTTP vs HTTPS.

Cyber Safety (2021, 2023, 2024)

Q: What is phishing? How can you protect yourself? (2 marks)
Answer: Phishing = fraudulent emails/sites that steal credentials. Protection: verify sender, don't click unknown links, use 2FA. Also asked: malware types, firewall, strong password.

Python — Lists & Tuples (2021, 2023)

Q: What is the difference between a list and a tuple in Python? Give examples. (2 marks)
Answer: List — mutable, [1,2,3]; Tuple — immutable, (1,2,3). Tuples are faster; use tuple for fixed data. PYQ also: append(), remove(), slicing.

📋 PYQ Pattern (2019–2024): Python code-writing = 15–20 marks every year. SQL queries = 8–10 marks. HTML = 5–8 marks. Networking/Cyber Safety = 6–8 marks. Prioritise Python + SQL = 55% of the paper.

❌ Mistake Bank — Computer Applications

Most common errors in Comp App boards — catch these before the examiner does

Python — Indentation Errors

Mistake: Writing function body without consistent indentation — Python throws IndentationError.
Fix: Always use 4 spaces (or 1 Tab) consistently. The most common reason for zero marks in a code question is indentation mismatch.

SQL — Missing Semicolon / Wrong Quotes

Mistake: Writing string values with double quotes in SQL — WHERE Name="Ram" is wrong. SQL uses single quotes: WHERE Name='Ram'.
Fix: String values = single quotes. Column names / keywords = no quotes. Every SQL statement ends with semicolon.

Python — range() Off-by-One

Mistake: Writing range(1, n) when you mean to include n — range(1,n) gives 1 to n-1.
Fix: range(1, n+1) gives 1 to n. Always trace your loop with a small value of n before writing final answer.

HTML — Unclosed Tags

Mistake: Opening <table> without closing </table>, or <tr> without </tr> — loses 1 mark per unclosed tag.
Fix: Write opening and closing tags together first, then fill the content. Count <tr> = count </tr>.

Networking — Confusing Terms

Mistake: Writing "IP address is the physical address" — IP is logical, MAC is physical.
Fix: IP = logical (can change), MAC = physical (hardware, fixed). DNS converts domain name → IP address. HTTP = port 80, HTTPS = port 443.

Python — print() vs return

Mistake: Using print() inside a function when question asks to "return" the value — both look correct but only return passes value back to caller.
Fix: If question says "function should return", use return. If it says "display", use print(). Read the question keyword carefully.

📓 Code Tracing Strategy: For every Python program you write in exam, trace it mentally with a simple example (e.g., n=5, list=[3,1,4]) before writing. This catches 80% of logic errors before submission.

👁️ Examiner's Eye — Computer Applications

What the CBSE Comp App examiner checks — code quality, SQL syntax, marks allocation

Python Code Marking (3-mark)

CBSE marks: Correct function definition (1) + Logic/algorithm (1) + Output/return (1) = 3 marks.
Even if output is wrong, you get 2 marks for correct function header and logic. Never leave code blank.

SQL Query Marking (2-mark)

CBSE marks: Correct table/column names (½) + WHERE/GROUP BY clause (1) + ORDER/function (½) = 2 marks.
Examiner overlooks case differences (SELECT vs select) but not wrong clause names.

HTML Code Marking (3-mark)

CBSE marks: Correct structure tags (1) + Required tags present (1) + Attributes correct (1).
Write HTML tags in CAPS for visibility — examiner preference. Close every tag properly.

Definitions (1-2 mark)

Examiner looks for: Subject-specific keywords. For firewall: "barrier", "network", "filter". For malware: "malicious software", "damages". Don't write long paragraphs for 1-mark answers.

Flowcharts / Algorithms

Examiner checks: Start/End = oval. Process = rectangle. Decision = diamond. Arrow direction. If asked for flowchart, draw it neatly with proper shapes — even rough shapes with correct labels earn full marks.

Output Questions

Most common trap: Writing the output with wrong spacing or extra blank lines. Trace print() calls carefully — Python's print() adds newline by default. print("Hi", end="") does NOT add newline.

🎯 Examiner Secret: For code questions, write a comment line above each block — # Function to find maximum. CBSE examiners appreciate structured, commented code and it shows you understand the logic even if output has minor errors.

🔥 High-Probability — Computer Applications

Topics that appear in CBSE Comp App board every single year — guaranteed marks

📌 Python String/List Programs — 98% probability

Every year: Count vowels, reverse string, check palindrome, find max/min in list, count even/odd numbers.
Prepare all 8: These 8 programs cover 12–15 marks. Write each from memory 3 times before exam.

📌 SQL SELECT with WHERE/ORDER BY — 95% probability

Every year: Filter rows using WHERE, sort using ORDER BY, aggregate with SUM/AVG/COUNT.
Must know: SELECT-FROM-WHERE-GROUP BY-ORDER BY sequence. Aggregate functions: SUM, AVG, MIN, MAX, COUNT.

📌 HTML Table / Form — 90% probability

Every year: Create table with border and colspan/rowspan, or create a form with text boxes and radio buttons.
Must know: <table>, <tr>, <td>, <th>, border, colspan attributes.

📌 Networking Terms — 92% probability

Every year: LAN vs WAN, IP address, DNS, Firewall, HTTP vs HTTPS, topology types (Bus, Star, Ring).
Quick revision: All definitions in 1 line each. These are 1-2 mark questions — fast marks.

📌 Cyber Safety — 88% probability

Every year: Phishing, malware types (virus/worm/trojan), cyberbullying, safe browsing, strong password rules.
Examiner favourite: "What is phishing? How to protect?" — 2-mark question, appears 4/6 years.

📌 Python Functions & Scope — 85% probability

Every year: Define function, call it, return value vs print. Local vs global variable. Default arguments.
Prepare: Write 5 complete function definitions from memory — max(), count(), reverse(), factorial(), isPrime().

🎯 Top-3 Guaranteed Topics: (1) Python programs (string/list) — 15 marks (2) SQL queries — 10 marks (3) HTML table/form — 8 marks. These three alone = 33 marks. Master them and you're at 33/50.

⏱️ Last-Minute Revision — Computer Applications

48 hours before the exam — Comp App revision checklist

🐍 Python Quick-Recall

Write these from memory (no notes):
• Count vowels in string
• Reverse a list using slicing: lst[::-1]
• Check palindrome: s == s[::-1]
• Fibonacci series (n terms)
• Find largest in list without max()
• Count even numbers in a list

🗄️ SQL Quick-Recall

Write these 5 queries from memory:
• SELECT * FROM table WHERE condition;
• SELECT col, AVG(col2) GROUP BY col;
• SELECT col ORDER BY col2 DESC;
• SELECT COUNT(*) FROM table;
• SELECT col FROM t1, t2 WHERE t1.id = t2.id;

🌐 HTML Quick-Recall

Tag list to verify:
• <table border="1"> + <tr> + <td>/<th>
• <form method="POST"> + <input type="text">
• <a href="url">Link</a>
• <img src="pic.jpg" width="100">
• colspan="2" + rowspan="2" attributes

🌐 Networking Definitions

Memorise in 1 line each:
• LAN: Local Area Network — limited area, high speed
• WAN: Wide Area Network — large geographic area
• IP Address: Logical address assigned to device
• MAC Address: Physical address of NIC (hardware)
• DNS: Converts domain name to IP address
• Firewall: Monitors and filters network traffic

⏰ Exam Time Plan (2 hours, 50 marks)

Section-wise time:
Section A — MCQ (20×1): 15 minutes
Python programs: 30 minutes
SQL queries: 20 minutes
HTML: 15 minutes
Definitions/theory: 15 minutes
Check + attempt blanks: 5 minutes

✅ Last-Minute Checklist

✅ 6 Python programs written from memory
✅ 5 SQL query types practised
✅ HTML table + form structure memorised
✅ Networking definitions (LAN/WAN/IP/DNS/Firewall)
✅ Cyber safety terms (phishing/malware/firewall)
✅ Python syntax: correct indentation, colons after def/if/for
✅ 1 mock paper timed in 2 hours

⏱ Comp App Last Tip: In the exam, write the Python program first (even rough), then trace it with a small example before writing the fair copy. This 2-minute trace saves 3 marks every time.

🎮 Exam Simulator

MCQ drill — 35 questions, timed, auto-scored with visual score dashboard

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