Decreasing (k2tog)

If you decrease the number of stitches on your needle, it will make your knitting narrower. You'll using decreasing on the bird wings, as the wing shape tapers in towards the tip.

There are many different decreasing techniques in knitting, but the only one that I use in my patterns is called k2tog - you're knitting 2 stitches together.

This decrease is very similar to the knit stitch, only instead of picking up the loop of one stitch and knitting it, you'll be picking up 2 loops and knitting them at the same time.

Here's a helpful knitting tutotial video from The Blue Mouse Knits, which explains how to k2tog:

As an example, the tip of Barry the Puffin's wing has the following:

Row 27: k1, k2tog, k2tog, k1 (4 sts)

So with this row, you'll be knitting 1 stitch, then knitting 2 stitches together, then knitting 2 stitches together again, then knitting 1 final stitch.

You'll have started off with 6 stitches on your needle, and then because you worked 2 decreases, you now have just 4 stitches.