Python ProgrammingFrom Basics to Advanced Concepts

Module 1 – Python Basics

Understand what Python is, how to install and run it, and how to work with variables, data types, casting, comments and I/O.

1. Introduction to Python

Definition: Python is a high-level, interpreted programming language known for its clear syntax, readability, and wide use in web development, automation, data science, scripting, artificial intelligence, and general-purpose programming.

Why Python is popular

• Easy to read and write.
• Great for beginners.
• Large standard library.
• Huge ecosystem of third-party packages.
• Useful in many domains.

Example use cases

• Building websites
• Data analysis
• Automation scripts
• Machine learning
• File processing

2. Installing Python and Running Code

Python can be installed from the official Python website. Once installed, you can run code in the interactive shell,

1.py

Running a script:

1python hello.py

Example file:

1print("Hello, World!")

3. Hello World

1print("Hello, World!")

Explanation

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  1print()

  displays output on the screen.
• The text inside quotes is a string.
• This is the simplest Python program.

4. Syntax and Indentation

Python uses indentation to define code blocks instead of braces.

1if 5 > 2:
2    print("Five is greater than two")

• The colon
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  1:

  starts a block.
• The indented line belongs to that block.
• Indentation is mandatory in Python.
• Do not mix tabs and spaces in the same block.

5. Variables

Definition: A variable is a named container used to store a value.

1age = 18
2name = "John"
3print(name)

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  1age

  stores an integer.
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  1name

  stores a string.
• Python does not require explicit type declarations.

Variable naming rules

1age

11age

1my_name

1my-name

1total1

1class

1is_active

Use meaningful names, prefer lowercase with underscores, and avoid reserved words.

6. Basic Data Types

Python has several built-in types.

7. Strings, Numbers, Booleans

1hello = "Hello World"
2multi_string = """Multiline
3Lorem ipsum dolor sit amet,
4consectetur adipiscing elit"""
5 
6x = 1          # int
7y = 2.8        # float
8z = 1j         # complex
9 
10my_bool = True
11print(bool(0))  # False
12print(bool(1))  # True

8. Type Checking and Casting

1x = 1
2print(type(x))       # <class 'int'>
3 
4x = int("3")
5y = float("4.2")
6z = str(2)

• Type checking helps you understand what kind of value a variable contains.
• Casting converts one data type into another.

9. Comments

1# This is a single-line comment
2print("Hello World")  # inline comment
3 
4"""
5This is a multi-line comment
6used for documentation.
7"""

10. Input and Output

1name = input("Enter your name: ")
2print("Hello,", name)

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  1input()

  waits for user input.
• The returned value is always a string.

11. Arithmetic Operations

1result = 10 + 30    # 40
2result = 40 - 10    # 30
3result = 50 * 5     # 250
4result = 16 / 4     # 4.0 (floating-point division)
5result = 16 // 4    # 4   (floor division)
6result = 25 % 2     # 1   (remainder)
7result = 5 ** 3     # 125 (exponent)

Compound assignment:

1counter = 0
2counter += 10
3message = "Part 1."
4message += "Part 2."

12. Formatted Output

1name = "John"
2age = 23
3 
4# %-style
5print("%s is %d years old." % (name, age))
6 
7# .format()
8print("My name is {}, I'm {}".format(name, age))
9 
10# f-strings (preferred)
11print(f"My name is {name}, I'm {age}")
12num = 10
13print(f"{num} + 10 = {num + 10}")

Module Recap

• What Python is and why it is used.
• How to write and run a simple Python program.
• How indentation controls structure.
• How variables, data types and casting work.
• How to print output and accept input.
• How basic arithmetic and formatting work.