Overview
Functions reusable code blocks hain bhai — ek baar likho, baar baar use karo.
Analogy
Function ek machine ki tarah hai — input do (parameters), processing hogi, output milega (return).
Step-by-step
- def function_name(parameters): se define karo
- Body mein kaam karo
- return se value wapas bhejo
- function_name(args) se call karo
Visual
def greet(name):
return f"Hello, {name}!"
print(greet("Alice")) # Hello, Alice!
Common mistakes
- Return statement bhool jaana — None return hoga
- Parameters aur arguments ka confusion
- Function define hone se pehle call karna
Practice questions
- Area calculate karne wala function banao
- Temperature converter function banao (C to F)