What the hell are blur, space compression and perspective in photography?

Fuzzy means that the background is blurred and the foreground is clear or the foreground is blurred and the background is clear; Spatial compression is a kind of spatial compression in which a distant subject is photographed with a telephoto lens, and the background behind the subject looks closer to the subject. There are two understandings of perspective. One is perspective composition. For example, if you shoot from the left to the right of a row of fences, there will be perspective, or if you shoot at one end of the corridor, the other end will also be perspective. Another understanding is that the lens is distorted and a subject is photographed at close range. The subject looks big near the lens and small away from the lens.