Ubuntu - Video - About Video

Almost all the video is compressed.

Raw, uncompressed video is just too big and would waste too much bandwidth.

Common compression:

After H.264 came H.265. It also has a few other names, most commonly High Efficiency Video Coding (HEVC) or MPEG-H.

H.265 doubles the data compression ratio compared to H.264 and can support resolutions up to 8192×4320.

This means that video at the same quality needs only half of the bandwidth (or file size).

Alternately, it means that the quality of the video can be substantially improved at the same bit rate, something very important for very high definition (i.e. 4K and 8K) displays,