What type of device is typically connected using a Digital Visual Interface (DVI) port?

A Digital Visual Interface (DVI) port is primarily used to connect video display devices to a computer's graphics card. It is designed for optimizing the visual display quality of digital images, making it particularly suitable for flat-panel displays such as LCD and LED monitors. The DVI connection supports high-resolution video formats and is often found on various types of monitors and projectors.

While external hard drives, printers, and keyboards are essential peripherals, they do not rely on DVI connections. External hard drives typically use USB or Thunderbolt interfaces for data transfer, printers commonly utilize USB or network connections, and keyboards connect through USB or Bluetooth technology. Therefore, the type of device that is most commonly associated with a DVI port is indeed a form of flat-panel display.