A buttonhole is a reinforced hole in fabric that a button can pass through, allowing one piece of fabric to be secured to another. The raw edges of a buttonhole are usually finished with stitching. This may be done either by hand or by a sewing machine. Some forms of button, such as a frog, use a loop of cloth or rope instead of a buttonhole.

A button is a fastener that joins two pieces of fabric together by slipping through a loop or by sliding through a buttonhole.