Very simply 50mm = standard 1 to 1, what you see visually is what you get on film.
anything below 50mm and the angle is getting wider, anything over and the field is larger enlarged and thus smaller,
usually a good sized lens for wide angle work is around 24mm, though anything between 14mm and 35mm are generally used in 35mm film format.
of course you can get very special "fish-eye" lenses with 6 or 8mm.
With modern digital cameras you would multiply the focal length by anything from 1.5 (Nikon) to 2.
Therefore the focsl lengths are usually much shorter on digital lenses, to achieve a true wide angle you would be looking at 12 to 16mm with Digital lenses.