The ABSOLUTE VALUE of a number is its distance from zero on a number line. It is ALWAYS expressed as a POSITIVE number.
|-4| = 4 and |4| = 4
Absolute value can be thought of as a measurement or distance. The concept of a direction or a sign (i.e. positive or negative) is not relevant.
For instance, SPEED is a raw measurement of a rate (distance over time) without regard to direction. VELOCITY indicates BOTH speed and direction. A rocket launches UP into space with positive velocity and returns DOWN to earth with negative velocity. Its speed in both cases would be referred to as simply a positive number.