I read somewhere that I trust
"You should set your editor to emit spaces when you hit the tab key. "
But the resource doesn't explain why and I can not ask them!
The only thing that comes to my mind is that when you want the code to be of minimum length, because you want to be used on the internet, like jQuery for example, then you parse the file and you remove all spaces. However, I think that this is not it, because how hard would it be to say to the program that removes the spaces, to remove tabs too.