Is the absolute value function a metric? I was trying to find out more information about absolute value, and I came upon the fact that AV satisfies a whole set of properties that usually defines a distance function or metric. But in the Wikipedia article on metrics, there's no mention of the AV function, so I'm a bit confused now. Is it some sort of metric subspace instead?
P.S.: I'm not at all well-versed on metrics, so I'd appreciate simple answers :)

The absolute value $x\mapsto |x|$ is not a metric but a norm on $\mathbb R$ (or $\mathbb C$), viewed as a one-dimensional vector space. However, from any norm you can derive a metric in a standard way.
In the case of the absolute value, this gives the well-known metric $d(x,y)=|x-y|$.
