HDMI and VGA - also known as High Definition Multimedia Interface and Video Graphics Array/Adapter - are two common video standards widely used today. Though both transmit data across cables, the major difference between the two interfaces lies in the format of the data they transmit. VGA cables are the industry standard for channelling analogue data signals while HDMI cables lead the industry in digital signal transmission.
The VGA interface was originally designed by IBM for their computer systems in 1987: VGA cables were primarily used to send video-only signals from a device - typically a PC - through to a display - typically a monitor. HDMI cables ,however, were developed for consumers in 2003 in an effort to streamline the transmission of numerous, complex digital signals between various HD capable devices, such as those sent from Blu-ray players and set-top boxes to plasma screen TVs and LCD monitors.
As VGA cables are only able to carry a single analogue video signal at a maximum resolution of 640×480 pixels, another cable is required to transmit separate signals such as audio. Though converting the signal from a Standard Definition analogue format to an HD digital one is possible, the process significantly strips the already lacking original signal of its quality and clarity. In contrast, HDMI cables possess vastly superior transmission capabilities: they can process High Definition video at resolutions of 1920×1200, along with eight additional High-Quality audio channels simultaneously. Essentially, one HDMI cable can effectively perform the task of three extra cables.
VGA cables have one connector type and are prone to crosstalk - that is, signal interference from other cables. There is also a noticeable degradation in signal quality over extensive cable lengths. Contrastingly, with five different connector types for a vast number of displays and devices, even the most basic HDMI cable offers exceptional connectivity and signal shielding at long cable lengths.