You can make an extra stitch by making a yarn over on the right needle. If the yarn over is knitted or purled on the next row/round, you will get a hole; if the yarn over is worked twisted on the next row/round, then the hole will become smaller.
synonyms: YO, yarn round needle
category: technique
How to increase 1 stitch x 2 with yarn overs from right side, which are purled or purled twisted