The Mini HDMI adapter can be used if you have a camera with a mini HDMI connector that you would like to turn into a normal HDMI connector. This adapter has a small crack, so it's easier to get into the device. 

You can also use the adapter if you want to record raw video from your Canon camera to an external recorder. This with the crack can be easily attached to the camera with duct tape.

The Mini HDMI to HDMI adapter lets you use to plug your camera with Mini HDMI connectors for your TV. 

Canon's DSLR camera often uses Mini HDMI, e.g. using the Canon EOS 1100D, Canon EOS 1200D, Canon EOS 1300D, Canon EOS 100D, Canon EOS 550D, Canon EOS 600D, Canon EOS 650D, Canon EOS 700D, Canon EOS 750D, Canon EOS 760D, Canon EOS M3, Canon EOS 60D, Canon EOS 70D, Canon EOS 80D, Canon EOS 6D, Canon EOS 7D, Canon EOS 7D mark 2, Canon EOS 5D mark 2, Canon EOS 5D mark 3, Canon EOS 1D X, Canon EOS 1D X mark 2, Canon EOS 5DS R, Canon EOS 5DS all HDMI mini. 

Canon calls this cable the Canon HTC-100. 

Mini HDMI is also called HDMI Type C, this adapter is based on HDMI 1.4, i.e. it supports 4k up to 24/30Hz and 1080p up to 120Hz, as well as a lot of other HDMI features.

Rasberry pi zero also uses this connector.

There are also a lot of Sony and Nikon camera that use Mini HDMI.