Skip to main content

Case Sensitivity

Python is case-sensitive:
variable = 1
Variable = 2  # Different from 'variable'

Installation & Setup
Download from python.org

Verify installation:

bash
python --version
# or
python3 --version
Running Python
Scripts: python filename.py

Interactive: python or python3 in terminal

IDEs: VS Code, PyCharm (best for large projects)

Notebooks: Jupyter (best for data analysis)

Brief History
Created by Guido van Rossum in 1991. Named after Monty Python. Emphasizes code readability.

Variables
python
# Basic assignment
name = "Alice"  # str
age = 25        # int
price = 9.99    # float
is_active = True # bool

# Multiple assignment
x, y, z = 1, 2, 3
Functions
Basic Function
python
def greet():
    print("Hello!")
With Parameters
python
def greet(name):
    print(f"Hello, {name}!")
With Return Value
python
def add(a, b):
    return a + b
Default Parameters
python
def greet(name="Guest"):
    print(f"Hello, {name}!")
Data Types
Numeric
python
int_num = 10       # Integer
float_num = 10.5   # Floating point
complex_num = 1j   # Complex
Sequence Types
python
list_ex = [1, "two", 3.0]  # Mutable
tuple_ex = (1, "two", 3.0) # Immutable
range_ex = range(5)        # range(0, 5)
Text Type
python
string = "Hello World"
Boolean
python
true_val = True
false_val = False
Set Types
python
set_ex = {1, 2, 3}         # Unordered, unique
frozen_set = frozenset({1, 2, 3})  # Immutable set
Dictionary
python
dict_ex = {"name": "Alice", "age": 25}
Type Conversion
python
int("10")       # String to integer
str(10)         # Integer to string
float("10.5")   # String to float
list((1,2,3))   # Tuple to list