Sweep rowers (one oar per person) and scullers (two oars, one in each hand) have similar stroke styles, with some differences to accommodate the number of oars held by the rower. The most notable difference is that the oar handles overlap in sculling at the midpoint of the drive, and again during the recovery. This requires the sculler to cross one hand over (left over right) and/or in front of the other hand to avoid the oar handles colliding. While sculling is a fully symmetrical movement (with exception of the handle overlap), sweep oar rowing is slightly asymmetrical and many rowers strongly prefer one side to the other.