You what?!?

Incel - what the heck is that then?  I'd never come across it before the recent incident in Vancouver when the driver of a van mounted the pavement and ran several pedestrians down.  Searching for a motive, the authorities came across a post on Facebook by the supposed driver of the van referring to "the incel rebellion".  It apparently is short for involuntarily celibate, and refers to men who are still virgins, though not through choice.  Not quite sure what their beef is - they seem to have a hatred of those who do have a sex life, who they refer to as "Chads and Stacys", and they seem to align themselves politically with the "alt-right" although I'm blowed. if I can see the connection.  Perhaps all will become clear in due course