Types of Flies
Flies or fly patterns (same thing!) come in a wide variety of styles, colors, and sizes for countless species. Flies can be specific imitations of various prey or simply "attractors" that try to provoke strikes with unique colors or movement. Although many flies are more commonly referred to by their specific style or name, for simplicity's sake, let's go over a few of the most general categories you should be familiar with.
While the term "dry fly" usually brings up images of a small insect-imitating trout fly, any fly made to float on the water's surface is technically a dry fly. These flies come in many sizes and styles, from ultra-tiny insect imitations to massive creations made for saltwater fishing. A few examples of specific subcategories of dry flies include attractors, terrestrials, and poppers.
A fly that's fished (you guessed it!) under the surface can be labeled a wet fly. Like dry flies, various types of wet flies exist, from old-school traditional patterns to nymphs and countless others! Speaking of nymphs, they are a prevalent type of wet fly—especially with trout anglers. Nymphs resemble immature insects and are popular for trout and other freshwater species such as panfish, carp, and steelhead. In addition, wet flies may often be weighted with things like lead wire, eyes, or bead heads to help them sink even faster.
A streamer is another popular type of wet fly that can catch many fresh and saltwater species. Flies in this category often have long hair/fibers for increased action because they can imitate large, lively prey like small fish and leeches that big fish feed on. A streamer is typically cast out and then retrieved by stripping in the line, which means the angler will likely feel the actual strike. The hits can be jolting, and the rewards can often be substantial!