You can't start a fly without something to put the assorted materials on. This makes a hook the foundation of every fly. You have hooks for every different type of fly. Dry fly hooks are made of wire that is light in weight so the flies will float. Nymph and streamer hooks are made heavier than dry fly hooks and are called 2x or 3x in weight. Hooks also may have different lengths. Some streamer hooks used to make classic Rangeley style streamers are as long as 8 or 9x. There are many different shapes in hooks also. While most hooks have straight shanks, those that are used in making realistic nymph flies have curved shanks. There are long and slightly curved hooks to make stonefly and Stimulator patterns and long drooping shanks for the Klinkhamer and other emergers. There are also special barbless hooks designed to hold fish without the use of the traditional barb. We carry hooks from the following manufactures. Mustad, Daiichi, Lightning Strike, Partridge, Gaelic Supreme and Firehole.
Here is a chart that compares hooks of the different manufactures.