Variables:
- Identity given to memory location
- Variables store program data.
- Variable value can be modified.
Note: In Python, no need to specify the data type in variable declaration
- Variables are created by assigning a value to a name.
- x = 5
- Variable names in Python can contain letters, numbers, and underscores, but cannot begin with a number.
- my_var = 10
- var_2 = “Hello, world!”
- Python is case-sensitive, so my_var and My_Var are considered different variables.
- Variable names should be descriptive and not too long.
- For example, total_sales is better than ts.
- Variables can be reassigned to new values:
- x = 5
- x = 10
- Variables can also be used in expressions:
- x = 5
- y = x + 3
- Python supports multiple assignment:
- x, y, z = 1, 2, 3
- Underscores can be used to separate large numbers for readability:
- num = 1_000_000
- Python has several reserved keywords that cannot be used as variable names, such as if, else, while, and for.