In a nutshell, HDMI 2.0 is designed to handle more bandwidth than HDMI 1.4. Both can deliver 4K video, but HDMI 2.0 can transfer up to 18Gbps whereas HDMI 1.4 can only transfer up to 10.2Gbps. That extra bandwidth allows HDMI 2.0 to deliver a few extras that might have seemed unnecessary just a few years ago.