A purse seiner is a type of fishing vessel designed to catch fish using a large net called a purse seine. This net is deployed around a school of fish, and its bottom is drawn tight like a purse, trapping the fish inside. Purse seiners are commonly used to catch species such as tuna, sardines, and mackerel. These boats can vary in size, from small vessels to large commercial ships. Purse seiners are often equipped with advanced technology, including sonar and GPS, to locate fish more efficiently. This method of fishing is popular due to its effectiveness and ability to catch large quantities of fish quickly.