Transverse Electric Mode

I've been doing some recent research and studying on lasers and I was just wondering: what exactly is the difference between transverse electric modes? I understand popular diodes like the M140 may transition between different modes, but what exactly makes it so different?

All you ever wanted to know about transverse modes.
https://en.wikipedia.org/wiki/Transverse_mode

Transverse Electromagnetic mode.

Gadget's link is good.

Also a good page: https://www.rp-photonics.com/modes.html