Python Variables - Complete Guide

Python Variables - Basic Concepts

Variable ek naam hai jo kisi value ko represent karta hai. Programming mein variables important hote hain kyunki ye data ko temporarily store karte hain jise hum program ke andar use kar sakte hain.

Variable kaise banayein?

Python mein aapko declare karne ki zarurat nahi hoti, bas aapko variable ko ek value deni hoti hai:

age = 20
name = "Anil"

Variable ka naam karna chahiye valid

• Alphabet letters, numbers, aur underscore use kar sakte hain.
• Variable naam number se shuru nahi hona chahiye.
• Spaces nahi honi chahiye.
• Keywords jese if, for variable name nahi ho sakte.

Python me data type samjho

Python me variable data type change ho sakta hai dynamically. Kuch important data types hain:

• int - Pura number, jaise 10
• float - Decimal number, jaise 3.14
• str - Text, jaise "Hello"
• bool - True ya False

Example

name = "Anil"
age = 20
height = 5.8
is_student = True

print(name)
print(age)
print(height)
print(is_student)

Output

Anil
20
5.8
True

Variables ko practice karna important hai! Aap alag alag values daal kar program chalaiye.

Python Variables - Detailed Explanation

Python mein variable ek naam hai jo memory mein data value store karta hai. Programming mein har value ko uniquely identify karne ke liye variables ka use hota hai.

Variable naming rules

• Variable naam letters (A-Z/a-z), digits (0-9), aur underscore (_) include kar sakta hai.
• Naam number se shuru nahi hona chahiye. (e.g., 1name galat hai)
• Spaces nahi honi chahiye variable name mein.
• Keywords jaise if, while variable naam nahi hote.
• Variable names case-sensitive hote hain, matlab age aur Age alag hain.

Value Assign karna

Python mein value assign karne ke liye = operator ka use karte hain:

count = 5
name = "Rahul"
price = 29.99

Dynamic typing ka matlab

Python mein variables ko declare nahi karna padta; type runtime par value ke hisaab se ban jaata hai. Aap ek variable ki value baad mein bhi change kar sakte hain:

var = 10   # var ab int hai
var = "Hello"  # ab var string ho gaya

Common Data Types

• int: Pura number (e.g., 4, -10)
• float: Decimal number (e.g., 3.14, -0.5)
• str: Text data (e.g., "Python")
• bool: True ya False

Variables ka Scope

Variable ka scope uske usage ki limit hoti hai. Do tarah ke scopes hote hain:

• Local variables: Jo function ke andar banaye jate hain aur sirf usi function mein accessible hote hain.
• Global variables: Jo function ke bahar banaye jaate hain aur poore program mein accessible hote hain.

Multiple Variable Assignment

Aap ek saath multiple variables ko values assign kar sakte hain:

a, b, c = 5, 10, 15

Ya sabko ek hi value de sakte hain:

x = y = z = 0

Examples

name = "Sita"
age = 22
height = 5.6
is_student = True

print("Name:", name)
print("Age:", age)
print("Height:", height)
print("Student:", is_student)

Output

Name: Sita
Age: 22
Height: 5.6
Student: True

Conclusion

Variables programming mein bahut important hain. Python kafi flexible aur easy language hai variables ko handle karne mein. Aap jitna practice karenge, utna achha samajh ayega.