1.Two-Person Standing (also called the trust lean): Both people are standing, standing some distance away. The person in front (the faller) falls and the person behind (the spotter) catches them. Either the spotter can catch the faller by his/her armpits, or (if they are close enough) the spotter can put his/her hands on the faller's back to stop his/her fall.
2. Three-person kneeling: The faller stands, but there are two spotters behind the faller on one knee. The spotters catch the faller with their hands raised behind the faller's back.
3. Group: There are different variants of this, but the most known is this: The faller stands on the edge of an elevated plane, like a table, with a group of spotters standing behind him or her in 2 lines on either side. The spotters hold their arms outstretched as they catch the faller.