Read/write/execute file permissions.

Having them set incorrectly can cause problems, such as creating a file as root then leaving you unable to modify it as user, being unable to execute a script because execute is not set, or being unable to use your SSH keyfile because you left the permissions too open.

It’s more actually like “Why is it, when something doesn’t happen, is it always you three”

The batteries are for dipping

The answer is very much “Don’t run Photoshop”

(Fuck Adobe. There, I said it)