Learn to Knit - Ribbing
Ribbing forms a stretchy band and is usually found at the bottoms of sweaters, sleeves, neckbands, hat brims and mitten cuffs, and at the tops of socks. When worked as an edging, ribbing is generally worked with smaller needles than the main body of the garment to keep the edges firm and elastic.
Ribbing can be worked as K1, P1 ribbing; K2, P2 ribbing; or any combination of stitches that will be specified in the pattern.
(1) To make K1, P1 ribbing, Knit a stitch. Bring the yarn forward to the front of the work between the left and right needle
(2) and Purl the next stitch.
(3) Return the yarn to the back of the work between the needles
(4) and Knit the next stitch.
Alternate Knit and Purl stitches until the row is finished (or for however many stitches the pattern specifies).