Well, technically, H.265 goes by the name of HEVC,

Well, technically, H.265 goes by the name of HEVC, or High Efficiency Video Coding. As H.265's longer name implies, the video codec is designed to succeed H.264 with a more efficient encoding standard. That means it will support video files of 4K and 8K resolutions while simultaneously improving upon current streaming by cutting the required bitrate by up to 50 percent. The way it does this is relying on more specialized hardware and computing power--with improved compression algorithms and more time or a computer has to process a video, the more compact a video can be compressed without losing too much visual fidelity. H.265 will require more computational power than its predecessor, but the trade-off is a no-brainer. Computer processors, especially mobile CPUs, grow more powerful every year, but our network infrastructure and bandwidth speeds are growing much more slowly. HEVC theoretically will make current HD video streaming more efficient while paving the way for a future of 4K content.
http://www.tested.com/tech/web/453188-what-yo...265-video/
........good older article