Handjob
A handjob is manually stimulating a penis with the hand(s) — one of the simplest, most fundamental sex acts. It's much like masturbation, except a partner does the work, with endless room for different grips, strokes, speeds, and positions. It can be a complete act, a tease, part of foreplay, or fold into a dominance dynamic (guided, edged, or 'milked' on command). Lube, attention, and reading feedback turn it from basic to great. It's accessible, low-pressure, and easy to combine with anything else.
The giver has precise control — speed, grip, and rhythm all adjustable in real time — which makes it easy to tease, edge, or drive a partner over the edge. For the receiver, a skilled, attentive hand can be surprisingly intense, and there's intimacy in watching and being watched.
The giver wraps and strokes the shaft and head, varying grip, twist, and pace, often adding lube and their other hand at the base or on the testicles, and reads the receiver's reactions. It can be leisurely and teasing or brisk toward orgasm, and pairs easily with kissing or oral.
Very low-risk. Use lube to avoid friction and mind grip strength (the frenulum and head are sensitive). Watch nails, and keep any shared fluids in mind for safer sex.