In Before Banned
Usually said on forums when someone posts something against of terms of service for the website. In other words, it means 'i saw this topic before the moderators/admins banned you and deleted this topic'
Comes from the slang term 'b&' because b + and = band. '&' is 7 on the keyboard.
J0rg3Guy554: Check out this child porn!!11
YellowMan3563: ibb7!111 lolol