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---
id: variables
title: A Container for Data, Variables
description: The concept of variables and how to declare variables in Python
tags:
  - Variables
  - Python
  - Programming
  - Beginners
sidebar_position: 15
isPublic: false
---

# A Container for Data, Variables

In programming, a `Variable` is essentially a container for storing data.

You can assign a name to data to store a value, and you can modify or reference the stored value as needed.

<br />

## The Meaning of Variables

A variable is essentially a name that refers to a memory location used to temporarily store data and instructions.

In Python, you don't need any special keywords (e.g., `var`, `let`) to declare a variable. Simply use a variable name and assign a value with the equals sign (=).

```python title="Variable Declaration and Assignment"
my_variable = 10  # Assign 10 to the variable my_variable

name = "CodeFriends"  # Assign "CodeFriends" to the variable name

Declaring and Initializing Variables​

To declare a variable means to prepare the variable for use.

When declaring a variable, assigning a value to it is referred to as initialization.

Declaring and Initializing a Variable
# Declare the variable my_var
my_var = 10 # Initialize by assigning 10

In Python, if you declare a variable without initializing it, a NameError will occur.

Declaring a Variable without Initialization
# Attempt to declare a variable without initialization
x  # NameError: name 'x' is not defined

Therefore, when declaring a variable in Python, you must initialize it using the equals sign (=).


Characteristics of Python Variables​

  • Dynamic Typing: The data type (the form of data like text or numbers) of a variable is determined during the program's execution, and there's no need to pre-declare the variable type.

  • Reassignable: You can change the value stored in a variable or reassign it with a value of a different type.

Dynamic Typing and Reassignment
number = 5       # Assign an integer (number)

number = "five"  # Reassign with a string (text)

Coding Exercise​

Try assigning the string "hello" to the variable greeting.

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