HDMI is the acronym for high definition multimedia interface. It is actually a description of what the HDMI cable is used for. The cable provides the interface for high speed transmission of audio and video. The cable is used with audiovisual equipment such as HD televisions and Blu-ray DVD players. It looks similar to a USB cable, except for the fact that 19 individual wires are wrapped inside it.
HDMI cables are capable of transmitting 10.2 gigabytes per second. This is twice the normal bandwidth necessary for transmission of audio and video signals. HDMI is the only one mode which provides clean and uncompressed digital information. The other methods are analog.
What makes HDMI so special?
Analog signal transmission picks up digital data from a source and transmits it after converting it to analog data which is again converted to digital, before being displayed on screen. This triple conversion of the data causes it to break and the resultant final display of audiovisual signals is not clean. It has disturbances and is of lower quality than original signal. The HDMI cable keeps the original digital signal intact and eliminates the need for conversion. It gives you the clearest, sharpest images and audio.
HDMI cables are available in different versions such as HDMI 1.0, HDMI 1.1, HDMI 1.2, HDMI 1.2a, HDMI 1.3 and HDMI 1.4 etc. They all look identical and have the same connectors. Each newer version can accommodate data transmission of the lower levels. This means that you will not go wrong if you buy the HDMI cable of the latest version. All your equipment will work well, no matter what version of the HDMI cable you use.
Any older audio/video equipment you have will work together with any newer equipment regardless of which HDMI cable version you use.