This shirt isn't a programming language. rm -rf is a Unix command. The rm stands for remove (which you can think of as delete). The -r stands for recursive, meaning it will delete the contents of folders and their subfolders. The f attribute stands for force; using this will automatically remove the file without prompting you with "Delete xxx? Y/n". So this means delete /bin/laden. The thing that makes it even more funny is that /bin is an actual directory on many machines, making laden one of the binaries. Haha.