205-A Montezuma Rt. There are different types of variables. First, there is the integer type. An integer is any positive or negative number that does not have a decimal point. This leads us to a second variable type - the 'double'.
Doubles are numbers with decimal points.
Therefore, all the numbers in the second set of examples above are doubles. Third, there is the character type. To start with, each letter of the alphabet and each punctuation mark is a character. Note that '3' is an integer according to the example above but '3.0' is a double. Of course, '3' and '3.0' refer to the same value but to a computer they represent different types.