There are numerous advantages of using HDMI over analog but the main reason is quality. HDMI is a digital interface. It therefore provides excellent quality because there analog to digital conversion is not required as there is with component or S-video. At higher resolutions, such as 1080p, the impact is particularly noticeable. For example, there is no ghosting and only sharpness where there would be softness.
HDMI is extremely easy to use because it utilises video and multi-channel audio in just one cable. Using one cable versus many is less expensive and simpler. As HDMI is modern it is more future-proof so you can upgrade your equipment without needing to invest in further cables.
HDMI enters into a two-way dialogue between the video source, for example a DVD player, and the DTV, which means automatic configuration, for example is possible. HDMI will automatically communicate the best format to use format to use for the it is talking to, making it easier to use and less time consuming for consumers.