H.265 and H.264 are two video compression standards. H.265 manages to achieve the same video quality, and even more, as H.264 but at half the bit rate. 

In addition to reducing the final file size, H.265 offers many other advantages such as:

H.265 supports videos up to 8K at 300 fps (frames per second), while H.264 only supports videos up to 4K at 60 fps.
H.265 has better motion tracking algorithms than H.264.
H.265 has fewer errors and noise which increases image quality over H.264.
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