PBR textures usually offer fantastic results, but once you got a hold of them it can be hard to understand how to use them. Here's a quick guide for the Redshift renderer.
The Albedo map is the material's diffuse map (the color), but totally unshaded.
The ambient occlusion map, which is usually referred to as the AO, is not always included, but when it is, it should be connected as a color multiplier of the Albedo.
Displacement or Height