What's the difference between coaxial and SLR? Is an ordinary digital camera coaxial or paraxial or something?

Coaxial and paraxial are mainly distinguished according to the axis of framing. The difference between coaxial and SLR should be:

SLR is definitely coaxial, but coaxial is not necessarily SLR.

At present, many ordinary digital cameras have removed the optical viewfinder of the side axis, and most of them use the LCD screen to view. The image of the LCD screen comes from the lens, which is of course coaxial according to the viewing axis.