How To Knit Two Together | Red Heart
The simplest method of decreasing is to simmply knit or purl two stitches together as one. This is known as a knit two together (k2tog) or purl two together (p2tog). A k2tog will lean to the right, while the slip, slip, knit (ssk), a similar decrease, will lean to the left. Designers will specify which decrease to use, since the different directions can be design elements in the pattern.
Knit two together (k2tog): On a knit row, insert the tip of the right needle from left to right through two stitches instead of one stitch, then knit them together as one stitch.
Purl two together (p2tog): On a purl row, insert the tip of the right needle from right to left through two stitches instead of one stitch, then purl them together as one stitch.
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