A fish finder (also known as a fish locator or fish detection device) is a tool that uses ultrasound or similar technology to detect fish schools' location, size, depth, and other related information in the water. However, fish finders do not directly display the actual shape or appearance of the fish. Instead, they represent fish-related data through specific symbols or numbers.

On the display screen of a fish finder, fish are typically represented in the following ways:

Symbol Representation: Fish finders may use specific symbols (such as fish icons or crescent shapes) to represent fish schools or individual fish. The size, color, or shape of these symbols may vary depending on the fish's size or activity level. For instance, the Lucky fish finder uses three different fish icons of varying sizes to represent large, medium, and small fish. For a more intuitive view, users can set a crescent symbol to show fish, with the device typically offering two display modes: fish icons and crescent shapes.

Data Representation: In addition to symbols, fish finders also display data related to the fish school, such as the size of the fish (usually in centimeters or inches) and depth (usually in meters or feet). This information helps users better understand the fish school's location and characteristics.

It is important to note that due to the fish finder's working principles and limitations, the displayed fish school data may have some degree of error or uncertainty. Therefore, when using a fish finder, users should rely on their own judgment and experience to analyze and interpret the data.

In summary, fish on a fish finder are not displayed in terms of their actual shape or appearance but are represented by specific symbols, data, or both. This information helps users gain a better understanding of the fish school's location, size, and activity, ultimately improving fishing success rates.