What is HDMI?
HDMI (High-Definition Multimedia Interface) is the newest interface for audiovisual equipment such as high-definition television and home theater systems. With 19 wires wrapped in a single cable that resembles a USB wire, HDMI is able to carry a bandwidth of 5 Gbps (gigabits per second). This is more than twice the bandwidth needed to transmit multi-channel audio and video, future-proofing HDMI for some time to come. This and several other factors make HDMI much more desirable than its predecessors, component video, S-Video and composite video.

HDMI is an uncompressed, all-digital signal, while the aforementioned interfaces are all analog. With an analog interface, a clean digital source is translated into less precise analog, sent to the television, then converted back to a digital signal to display on screen. At each translation, the digital signal loses integrity, resulting in some distortion of picture quality. HDMI preserves the source signal, eliminating analog conversion to deliver the sharpest, richest picture possible.

Why do I need it?
Well, everything is going digital nowadays include new gaming systems like Wii and PS3. All those plasma, LCD, DLP HDTV you see at your favorite electronics store all have HDMI inputs and highly recommend you to use it. HDMI cables provides a one cable solution to transfer high quality digital video and audio. No need to color match those red, white yellow cables anyone!

I wonder what is next? Wireless HD signal transfer through satellite? Like we do not have enough frequencies running through our everyday life...geez

Notes for thought:
HDMI cables cannot go over 30ft without a HDMI repeater to boost signal. Regular home theather users like I usually stick with 6ft so no worries.

Techincal Note:
Our HDMI cables have alot of techincal specs but here are some to highlight and important.
Supports all HDMI Devices, including 1.3
Supports Resolutions up to 1080P
99.997% pure copper wires, 24k gold plated conductor to provide optimum
signal transfer. Triple-layer shielding rejects interference for the best EMI effect.
Conforms to HDMI 1.3 specification and is compatible with all HDMI devices
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