HDMI stands for High-Definition Multimedia Interface. It is a proprietary digital audio/video interface that carries uncompressed video and digital audio between devices such as TVs, game consoles, computers, and sound systems over a single cable.
The first HDMI specification was released in December 2002; later versions (including HDMI 2.2) raise bandwidth and supported resolutions while remaining backward-compatible with earlier gear. Source: TechTarget — What is HDMI?.