The only class documented in the component doc is UniversalClassLoader, which is deprecated as of 2.1 in favor of the ClassLoader one (or composer).

None of the 2.1+ classes (the ClassLoader being similar to the Composer autoloader and able to be configured from a composer-generated namespace map, and the different decorating cached loaders able to wrap both class loaders) are documented while they should be the one used.
Thus, documenting the cached loaders could be useful as this is where the component provides some additional value compared to the composer class loader.