I love electronic music, it's my biggest love as far as music goes but its an extremely varied style of music. For example Aphex Twin/Squarepusher etc are electronic music but have absolutely nothing in common whatsoever with Avicii or Calvin Harris, the musical styles are miles apart and the only thing they have in common was that they were created on computers.
"EDM" is a term primarily used to describe mainstream 'big room' dance music such as Martin Garrix, David Guetta, Laidback Luke, Marshemello etc. Its a term that was coined by American marketing execs when electronic music started to blow up big time in the US for the first time around 2007/2008, they needed a cool new term to market and sell the music to the kids and this is what they went with.
Ahh right! Now I gotcha, didn't realise it was coined differently. I see it mainly used as a umbrella term for a lot of subgenres of music now.