The way I explain this super simply to people is absolute value.

To most people, it just means that when you take the absolute value of a negative number it becomes positive, and the absolute value of a positive number stays positive.

Now there is more to it, but how you might think of absolute value instead is as a distance function, particularly how far away from zero you are on a number line.

This is way over simplified, but an example of how there can be a little more buried beneath the surface.