HEVC, also known as H.265, is a video compression standard designed for the newest generations of high-resolution video. It’s a successor to the widely-used H.264 codec (also called AVC or MPEG-4 Part 10) and offers some major improvements over that now-aging compression scheme.
Those high-definition images in 1080P resolution requires a better way to compress the data in order to transmit or store it. HEVC is twice as efficient as AVC (MPEG-4/H.264) and experiences only a minimal loss in quality.
HEVC’s lower bitrate will lead to less required bandwidth and storage capacity. A video of the same apparent visual quality would take up only 50% as much space. Alternatively, a video of the same size and bit rate could be significantly better looking.
With AVC, streaming at 1080P resolution will cost an impractical amount of bandwidth to create a lossless feed. With HEVC, those bitrate demands are reduced in nearly half, bringing 1080p resolution back to the table.