The majority of domestic knitting machines use latch needles, which have a hook and a hinged latch.

Closed latch
Opening latch
Fully open latch

They make stitches as follows:

• The needles are moved forwards by the carriage as it moves laterally across the bed.
• The latch is opened during this movement as it slides forwards through the stitch below that is still on the needle. (There are brushes on the carriage that also open the latches).
• The yarn feeder lays fresh yarn into the open hook.
• As the carriage moves further along the bed it retracts the needles.
• The latch is closed as it slides backwards through the stitch below that is still on the needle.
• As the fresh yarn is  pulled through the loop of the stitch below it creates a new stitch and allows the ‘stitch below’ to slide competely off the needle.