JS's == has some gotchas and you almost never want to use it. So === is what == should have been.

All examples are true:

"1" == true
[1, 2] == "1,2" 
" " == false
null == undefined 

It isn't that insane. But some invariants that you may expect don't hold.

"" == 0
"0" == 0
"" != "0"