The HDMI cables are able to transmit a clear and uncompressed digital signal at high speeds of up to 10.2 GB per second with their 1.3 versions and up. However, that should not lead you to believe that the input in the viewing area will always be superior to a digital-to-analog signaling component. Even though it can create a better display via its specific encoding and conversion methods, the end result can just as well be a totally pixilated image that you cannot make much of. The trick to attaining that true crystal clear and impeccable display also depends on the capacities of your device as well.
One of the most appreciated features of the HDMI is the CEC that enables user control over other devices connected via the remote control of, for example, the TV. However, this does not usually work very well with devices that do not include a HDMI interface. Therefore, users that have separate audio and video interfaces will either need to put some effort into adapting their system to the cables or purchase new equipment. The simplest way to make the necessary adjustments would be to purchase a cable that includes HDMI at one end and DVI at the end you connect to the device. However, even though you will obtain a better display, you will not have audio support.
It is important to note that the video signal you can get via the HDMI will have an enhanced appearance to S-video or non component video devices, in most cases. Whilst the last ones are limited to an aspect ratio of 4:3 and a resolution of 704×480 pixels, the HDMI in modern HDTVs can go as high as 16:9 aspect ratio and a 1920×1080 pixels. The reason for this is that whilst analog signals will travel as a constantly varying electrical current, the digital signals of the HDMI are commonly considered distinct electrical impulses.
Moreover, even though they are considered superior because they can transmit a full 1080p display, the truth is that you can get the same broadcasting via the component video cables, VGA and DVI as well. In addition, the length of the HDMI can pose problems when you do not choose the right bandwidth for it. Considering the information above, you simply cannot state that the HDMI is superior to other connections in all circumstances, but rather that it has some strong points in certain areas.