Canon's M (Also known as EOS-M) system is used for their APS-C crop sensor mirrorless lineup. It was announced in 2012 and was a late addition to the mirrorless market. M cameras are lightweight and simple to hold and use.
There aren't as many lenses available for the M system as Canon's other mounts, but the flange distance is only 18mm so adapting vintage lenses is easy. EF and EF-S lenses can also be used on M cameras with an optional lens mount adapter.