Right Side / Wrong Side
Right side and wrong side describe the two faces of knitted fabric: the right side is meant to show on the outside of the garment, the wrong side faces inward.
Explanation
The right side (RS) is the side of the fabric intended to show on the outside of the finished garment, while the wrong side (WS) faces inward or toward the body. In stockinette, the right side is the smooth side with clear V-shaped stitches, while the wrong side has a more 'bumpy' appearance. Patterns often specify which side you are working, especially in flat knitting, and it's wise to mark the right side with a safety pin or similar early in a project so you don't lose track after a break.