What is the difference between photographic cotton background cloth and key cloth?

This thing has no standard. My understanding is that there are two kinds of photographic cloth:

Background cloth printed with landscapes and patterns. What is needed is a background, which is usually used in a photo studio.

Solid color background cloth. Where necessary, there are ID card photos, portrait photos and so on. Because the background color is uniform, it is convenient for later matting, so it is also called matting cloth. -There are non-woven fabrics, background paper, velvet and so on. Non-woven fabrics are prone to moire and are not recommended; Background paper is relatively cheap, but it is not convenient to wear outside (it needs to be circled and easily broken); Personally, I still recommend velvet.