SSH/Shell

In Linux and Unix-style computer operating systems, root is the conventional name of the user who has all rights or permissions (to all files and programs) in all modes (single- or multi-user). Alternative names include baron in BeOS and avatar on some Unix variants. BSD often provides a toor (“root” backwards) account in addition to a root account. Regardless of the name, the superuser always has user ID 0. The root user can do many things an ordinary user cannot, such as changing the ownership of files and binding to network ports numbered below 1024. The name "root" may have originated because root is the only user account with permission to modify the root directory of a Unix system and this directory was originally considered to be root's home directory.