Stockinette stitch (also referred to as stocking stitch) creates a flat, smooth fabric that is very versatile. The knittingn will stretch amply and has a classic look.
Instructions (flat knitting)
Row 1: Knit all stitches
Row 2: Purl all stitches
Repeat these two rows
Instructions (knitting in the round)
Round 1: Knit all stitches
Repeat this round