Woman on top
Woman on top (also called cowgirl or riding position) is a group of sex positions in which the man lies back or sits. The woman straddles him facing either forward or backward. The man then inserts his erect penis into the woman's vagina or anus.
The cowgirl name comes from the image of the receiving partner "riding" the other partner the same way a cowboy rides a bucking horse. The position is often cited as one of the more popular sex positions, mostly by women.