Short rows are just as the name indicates– rows that are shorter than the number of stitches on the needles. They are often used to provide shaping, as for bust darts, and sometimes they are used for interesting color changes.
The most common time to see short rows is when shaping the shoulder portion of a fitted top.
Generally, you will work an indicated number of stitches, then turn the work as if you were at the end of the row, and continue working back to the beginning of the row. Quite often multiple rows are worked with less and less stitches each time. Usually, later in the knitting you will work back across all of the stitches.
Turning the work in the middle of the fabric can create a hole. The hole effect can be reduced in a couple of ways:
Wrap the yarn around the next unknit stitch before/as you turn the work. To do this, work up to the stitch indicated in the pattern, slip the next stitch without knitting it. Move the yarn to the opposite side from where it is (to the front if knitting, to the back if purling). Turn the work, slip the previously knit stitch back, and continue in the stitch pattern.
This creates a horizontal “wrap” of knitting around the unworked stitch. When you later work across all of the stitches, you should pick up the wrap and work it with the stitch it is wrapped around.
Yarn over
Similar to the wrap and turn, in this case you simply work to the number of stitches called for in the pattern, then turn the knitting. Work a yarn over and continue to work the row back.
When you later work across all of the stitches, you should work the yarn over together with the stitch next to it.
Working reverse short row shaping
Reverse short rows are when you have worked short rows already to move to a smaller number of stitches and are now going to increase back to a larger number. This can be necessary for a variety of reasons. I’ve seen it used on ear flaps in hats as well as cap brims. It is also used in some darts.
Knit across to the first wrapped st. Pick up the wrap and knit it together with the stitch on the left hand needle. Continue to the next wrapped stitch. Wrap and turn as usual (there are 2 wraps now at the turn). Purl across to the first wrapped stitch on the needle. Pick up the wrap and purl it together with the stitch on the left hand needle. Continue to the next wrapped stitch, wrap and turn (there are now 2 wraps at the turn). When working over a previous turn where there now are two wraps, pick up both wraps and work together with the stitch being worked. Continue in this manner until all stitches have been worked, as per directions.