The absolute value of a number is its distance from zero on a number line. For instance, 4 and –4 have the same absolute value (4).

So, the absolute value of a positive number is just the number itself, and the absolute value of a negative number is its opposite. The absolute value of 0 is 0.
Easy!
The absolute value of x is written as | x |. So,
|4| = 4
|–4| = 4
|54221.997| = 54221.997
|(–1/4)| = 1/4
See also: