The connector form of DVI

The DVI connector not only includes the digital signal pins specified by the DVI standard but can also incorporate the pins for traditional analog signals (VGA). This design is to maintain the universality of DVI so that different forms of displays can share the same connection cable.

Depending on the implemented functions, DVI connectors are divided into three types:
DVI-D (Digital; single link or dual link)
DVI-A (Analog)
DVI-I (Integrated; both digital and analog signals; single link or dual link)

In addition, connectors that implement the second group of DVI connections are called DVI-DL (dual link) to emphasize the transmission capacity.
Some newer DVD players, televisions (including HDTV), and projectors use so-called "DVI/HDCP" connectors. These connectors are identical in appearance to DVI, but the data sent is encrypted using the HDCP protocol to prevent illegal copying. Nowadays, computers with DVI interface graphics cards can often use the aforementioned display devices as large screens, but due to the fact that most graphics cards produced before 2007 do not support HDCP, they may be limited by copyright protection technology and unable to play HDCP-protected video content at the highest resolution.