Basic knitting terms include cast on and cast off, which refer to getting yarn on the needle at the beginning of a project and off at the end, and knit and purl, the two basic knitting stitches. Gauge, swatch and joining, other basics, deal with sizing stitches and adding yarn.
Gauge is the ratio of number of stitches per inch and per row and is tested by knitting a swatch, which is laid flat and measured to test consistency with pattern instructions. Joining refers to adding a length of yarn to another piece of yarn or to a work in progress.
Stockinette, garter, and cable are more advanced types of stitches, all related back to the knit and purl stitches. Increase and decrease in knitting craft refer to adding or removing stitches from a row of knitting and slip means to move a stitch from the left needle to the right needle without knitting into the stitch. Yarn over is an instruction to wind yarn around the needle one or more times before knitting the stitch.
Knitting instructions are abbreviated in patterns, such as CO, cast on; BO, bind or cast off; rep, repeat; and p2tog, purl two stitches together.