This is a backslash: \
It’s also known as a reverse solidus, oblique, slosh, hack, escape, reverse slash, backslant, backwhack, bash, reverse slant, reversed virgule, or backslat.
This, which is somewhat similar, is a forward slash: /
If you’re reading this in a web browser look up at the URL. It is full of forward slashes. Not a backslash to be found, right?
While working my way through the HP phone support system the recorded message instructed me to go to a URL with a bunch of backslashes in it - gives me a lot of confidence that they’ll be able to help me.
(Okay, I know I’m overreacting. I’m a slash snob. I shouldn’t judge people on their lack of knowledge when it comes to back and forward slashes.)