Stupid question [Parallax Occlusion Mapping]

Hi, this is a stupid question but few months ago I found documentation about a node in material editor that layers same texture multiple times one on top of each other to produce realistic look.
How is it called??

Before 4.9 you could do it to some extent using the BumpOffset node, examples of which you can find in starter content materials. But in 4.9 there is a function called ParallaxOcclusionMapping. You can find more info on it’s usage in this thread: POM material - Rendering - Unreal Engine Forums