Trawlers are fishing vessels designed to catch fish by dragging a large net, called a trawl, through the water. They can operate in various environments, from coastal areas to deep-sea regions, and are often equipped with powerful engines and advanced navigation systems. Trawlers can target different species, including cod, shrimp, and herring, depending on their design and fishing methods. There are two main types of trawlers: otter trawlers, which use weighted nets that are spread open by trawl doors, and beam trawlers, which use a beam to hold the net open. Trawling can be an efficient way to catch large quantities of fish, but it also raises concerns about overfishing and environmental impact.