Variables are containers that store data values - like labeled boxes that hold different items.

# Creating variables
name = "Alice"          # String (text)
age = 25               # Integer (whole number)
height = 5.6           # Float (decimal)
is_student = True      # Boolean (True/False)

print(f"Hi {name}! You are {age} years old.")

Data types classify data and tell the computer how to use it effectively.

print(type(25))        # <class 'int'>
print(type("Hello"))   # <class 'str'>
print(type(3.14))      # <class 'float'>
print(type(True))      # <class 'bool'>

Conditions allow programs to make decisions based on different situations.

age = 18

if age >= 18:
    print("You can vote! 🗳️")
else:
    print("Too young to vote")
    
# Output: You can vote! 🗳️

score = 85

if score >= 90:
    grade = "A"
elif score >= 80:
    grade = "B"
elif score >= 70:
    grade = "C"
else:
    grade = "F"
    
print(f"Your grade is: {grade}")  # Your grade is: B

Loops repeat code multiple times until a condition is met - perfect for repetitive tasks!

# Print numbers 0 to 4
for i in range(5):
    print(f"Count: {i}")

# Print items in a list
fruits = ["apple", "banana", "orange"]
for fruit in fruits:
    print(f"I like {fruit}")

# Count down from 5
count = 5
while count > 0:
    print(f"Countdown: {count}")
    count -= 1  # Same as count = count - 1
print("Blast off! 🚀")

Functions are reusable blocks of code that perform specific tasks - like mini-programs inside your program!

# Define a function
def greet(name):
    return f"Hello, {name}! 👋"

# Call the function
result = greet("Alice")
print(result)  # Hello, Alice! 👋

def calculate_area(length, width):
    area = length * width
    return area

# Call function with arguments
room_area = calculate_area(10, 12)
print(f"Room area: {room_area} sq ft")  # Room area: 120 sq ft

def introduce(name, age=18, city="Unknown"):
    return f"Hi! I'm {name}, {age} years old from {city}"

print(introduce("Bob"))                    # Uses defaults
print(introduce("Alice", 25, "New York"))  # All specified

Input/Output (I/O) allows programs to interact with users - getting information and showing results.

# Get user input (always returns string)
name = input("What's your name? ")
age_str = input("How old are you? ")

# Convert string to number
age = int(age_str)

print(f"Hello {name}! You are {age} years old.")

# Basic print
print("Hello World!")

# Print variables
name = "Alice"
print("Welcome", name)

# Formatted strings (f-strings)
age = 25
print(f"I am {age} years old")

# Print with separators
print("A", "B", "C", sep="-")  # A-B-C

# Simple calculator
num1 = float(input("Enter first number: "))
operator = input("Enter operator (+, -, *, /): ")
num2 = float(input("Enter second number: "))

if operator == "+":
    result = num1 + num2
elif operator == "-":
    result = num1 - num2
elif operator == "*":
    result = num1 * num2
elif operator == "/":
    if num2 != 0:
        result = num1 / num2
    else:
        result = "Error: Division by zero!"
else:
    result = "Invalid operator!"

print(f"Result: {result}")