Creating Variables
Unlike other programming languages, Python has no command for declaring a variable.
A variable is created the moment you first assign a value to it.
Example
x = 5 y = "John" print(x) print(y)
Output
Variables do not need to be declared with any particular type and can even change type after they have been set.
Example
x = 4 # x is of type int x = "Sally" # x is now of type str print(x)
Variable Names
A variable can have a short name (like x and y) or a more descriptive name (age, carname, total_volume). Rules for Python variables:
- A variable name must start with a letter or the underscore character
- A variable name cannot start with a number
- A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
- Variable names are case-sensitive (age, Age and AGE are three different variables)
Remember that variables are case-sensitive
Output Variables
The Python print
statement is often used to output variables.
To combine both text and a variable, Python uses the +
character:
Example
x = "awesome" print("Python is " + x)
You can also use the +
character to add a variable to another variable:
Example
x = "Python is " y = "awesome" z = x + y print(z)