How to Knit - Decreasing: Knit/Purl Two Together (K2tog / P2tog)
k2tog = knit 2 together
Work to the two stitches to be decreased and then knit the two stitches together as shown. The stitches slant to the right.
Purling two stitches together is done in the same manner. This decrease slants the stitches to the right.
Video Demonstration: K2tog
Video Demonstration: P2tog