Variables are basic building blocks of a programming language to store the value, reuse it in code, and modify the value.

Python Variables

Variables are names, assigned with a value, then reused the value in other places of a code.

It points to the memory location for the assigned value.

Variables in Python are dynamically typed values, which means variables are assigned a value without defining a datatype.

print(m); #20

Variables can be reassigned with new values as per give below example


variables can change their type by assigning a new value type


Multiple variables can be declared in a single statement using comma-separated

id, name, salary = 1, 'john', 4000

How to create a variable in Python

Variables are declared using name and value with assignment operator =.


str is declared and assigned with a value of name.

Variable naming convention rules

  • variables names either short or long
  • Python recommends names are in lowercase with underscore by convention, not compulsory
  • Usually, Variable names are identifier that always starts with either alphabets or underscore characters
  • alphabets contain a to z or 0-9
  • It does not start with a letter
  • Names are case-sensitive, variable names such as str, Str, STR are three different variables

Valid variable names are

  • number1
  • _price
  • total_value
  • _amount1

Invalid variable names are

  • 9amt
  • 21_proice
  • 111