Video narration
A sewing machine is basically a fast, guided way to make the same stitch over and over. Up top is the spool of thread. The thread travels through guides and tension discs, then down through the needle. When you press the pedal, the needle moves up and down, carrying the top thread through the fabric. Under the fabric is a second thread on a bobbin. As the needle starts back up, it leaves a small loop of top thread below the fabric. A hook under the needle grabs that loop and pulls it around the bobbin thread, like a quick lasso. When the needle rises, the machine tightens the threads, locking them together in the middle of the fabric. That’s one stitch. To make a seam, the presser foot holds the fabric steady, and feed dogs—little teeth under the foot—step the fabric forward the same distance each time. Needle, loop, hook, tighten, move: stitches in a straight line.