Daniel Arbuckle's Mastering Python

Variables

The second major building block of a Python program is called a variable. A variable is pretty much just a box for storing a data value. The variable has a name and we can use that name to access the data stored in the variable or to replace the data with a new value.

The function parameters in the previous examples were variables, as was area:

(name, radius):  

To set the data stored in a variable, we use an assignment statement. An assignment is a statement, so remember this means that it can't be combined with any other statement. It gets a line of source code all for itself and the expressions that are part of it.

An assignment statement consists of the variable's name on the left-hand side of an equal to symbol and the value ...