D-sub connectors are a type of electrical connector commonly used for connecting various devices, such as computers and monitors. They are named for their D-shaped metal shell, which provides a secure and stable connection. These connectors come in various sizes and pin configurations, allowing them to support different types of signals, including video, audio, and data. Typically, D-sub connectors are found in applications like serial and parallel communication, as well as in older video connections like VGA. Their robust design makes them reliable for both industrial and consumer electronics, ensuring a consistent connection in various environments.