Snell knot
The snell knot is a hitch knot used to attach an eyed fishing hook to fishing line. Hooks tied with a snell knot provide an even, straight-line pull to the fish. It passes through the eye of the hook, but primarily attaches to the shaft. It is a very secure knot, but because it is easily tied using only the near end as the working end, it is used to attach a hook only to a leader, rather than directly to the main line.
Hooks can be bought pre-snelled.