Yes, numbers can be classified as more than one type, and it’s not always easy to keep them straight. The following lists some ways to better understand the plethora of number types:

- A rational number is not always an integer: 4/1 is an integer, but 2/3 is not; but an integer is always a rational number—because it can be represented by a fraction by putting the integer over 1, or /1, such as 2/1 or 234/1.
- A number can either be rational or irrational but not both.
- The number for pi (3.141592…) is irrational (the decimal does not repeat) and real.
- 0.25 is considered rational (the numbers terminate) and real.
- The fraction 5/3 is rational (it’s a fraction) and real.
- The number 10 can be explained using many terms, including a counting number, whole number, integer, rational, and real.