Variables in Python

A variable in Python is a name given to a memory location that stores data or information.

The stored value can change during program execution, which is why it is called a variable.

For example:

X=10

Here, x is the variable name and 10 is the value stored.


What is a Variable?

A variable is like a container in the computer’s memory used to store data.

Instead of writing the same value many times, we:

Store it once , Reuse it many times

This makes programs:

• Easier
• Faster
• More organized

How Python Handles Variables

One reason Python for beginners is easy is that Python automatically understands the data type.

• Assign a number → Python treats it as a number
• Assign text → Python treats it as a string

Example:

age = 10
name = "VMS"

Python detects:

• 10 → Integer
• "VMS" → String

This feature is called dynamic typing.

Syntax

variable_name = value

The = symbol is called the assignment operator.

It assigns a value to a variable.

Explanation of Syntax

Practical Example

Think of a variable like a labeled box.

A box named x stores value 10.

x = 10
name = "VMS"

print(x)
print(name)

Output

10
VMS

Changing Variable Values

Variables can be updated anytime.

x = 10
x = 20

print(x)

Output

20

The old value is replaced by the new value.

Rules for Naming Variables

Valid Rules

Must start with a letter or underscore

name = "Ravi"
_value = 20

Can contain letters, numbers and underscores

student1 = "Ram"
total_marks = 90

Invalid Rules

Cannot start with a number

Wrong:

1name

Correct:

name1

No spaces allowed

Wrong:

my name

Correct:

my_name

Important Notes

Variables are case-sensitive

name = "Ram"
Name = "Ravi"

These are different variables.

Avoid Python Keywords

Do not use:

• print
• if
• for

as variable names.

➤ Why Variables are Important

Variables in Python help us:

• Store data
• Reuse values
• Solve problems
• Perform calculations
• Write flexible programs