Why does it matter what way the \ go

Answer 1

Well... It matters if you type a or b, so it matters if you type / or \ . These are all different characters.
Try it at the code playground.

\ is special: it is an escape sequence. Try
\n newline
\t tab
\? question mark
There are some more, but that will do for the beginning.

Answer 2

I never really thought of it like that before

Answer 3

Really the answer is because it does. Sorry but theres isnt a reason its just syntax