How do nets catch fish? What is the principle? What are the categories? I can't find the answer!

The nets have lead in them, and when the nets are thrown down, the nets spread out and fall into the water, and because the lead is heavy, it goes down vertically, and the fish are held in.

Fishing nets are functionally categorized as gill nets, trawl nets (drag nets), seine nets, build nets and lay nets. Requirements are high transparency (some nylon nets) and strength, good impact resistance, abrasion resistance, mesh size stability and softness, appropriate elongation at break (22% to 25%). Processed from monofilament, compound twisted wire (knotted mesh) or monofilament by braiding (raschel, which is a non-knotted mesh), primary heat treatment (to fix knots), dyeing and secondary heat treatment (to fix mesh size).

Expanded Information

Ancient people used coarse cloth and hemp as raw materials to make nets by bundling and rolling. Although this kind of fishing net is perishable and has poor toughness, its fishing efficiency has been greatly improved. With the development of fisheries, the object of fishing and hunting is not only fish, fishing tools have also advanced with the times. Modern fishing nets mainly use polyethylene, nylon and other raw materials for processing.

It has a longer life cycle, and higher fishing efficiency, through different ways of use for classification. For example, cast nets (hand nets, hand cast nets) are traditionally used for fishing, trawls are powered by boats, and drift nets (triple nets, purse seines) are used to trap fish with different mesh gills.

These nets are made of different sizes of mesh and different materials of netting for different fishing targets. The development of fishing nets has also led to the creation of a variety of fishing gear, such as fishing cages and trammel nets, which are commonly used as fishing tools.