Variables¶

Definition¶

Variables are areas in RAM where we can store one value. Each variable has a variable name (also known as an identifier). We use the variable name to refer to the value stored in the variable.

Note

A value could be a string, integer, floating point number or Boolean. For example, 'Adam', 5, 11.89 or True.

Easy example¶

name = 'Smith'

There is no output but “Smith” is stored in RAM. We say that "Smith" is assigned to the variable name.

Syntax¶

variableName = value

Examples¶

Example 1 - A variable to store a number¶

age = 15

Assigns 15 to age. The value 15 is stored in RAM.

Example 2 - A variable to store a name¶

playerName = 'Adam'

Assigns 'Adam' to playerName. The value 'Adam' is stored in RAM.

Example 3 - A variable to store the current state of a game¶

gameOver = False

Assigns False to gameOver. The value False is stored in RAM

Example 4 - A variable to store the result of a calculation¶

base = 20
height = 15
triangleArea = (1/2) * base * height
    print(triangleArea)

150.0

Key points¶

Note

The = symbol is known as the assignment operator. This is not the same as an equals symbol.

Warning

The value on the right of the = gets stored in the variable on the left. So 'Smith' = name will not work. The error that will appear is SyntaxError: can't assign to literal

Danger

You cannot use spaces in a variable name. For example, player name = 'Smith' will not work. The error that will appear is SyntaxError: invalid syntax

Hint

You can use two words for a variable name joing them together. For example, playerName = 'Smith' This is known as camel case.

Note

Python doesn’t have constants. For constants, simply make a variable and don’t change it!