Example image of eyePlorer eyePlorer map for 'Bourne shell': Thompson shell Unix shell Version 7 Unix AT&T Bell Labs Stephen R. Bourne Executable Superuser Unix Shell script Control flow Variable (programming) File descriptor Signal (computing) Parameter (computer science) Process (computing) Computerworld Here document Scripting language Brian Kernighan Rob Pike The Unix Programming Environment Error message ALGOL 68C University of Cambridge ALGOL 68 C (programming language) Macro (computer science) Source code Berkeley Software Distribution Finger protocol International Obfuscated C Code Contest C shell David Korn (computer scientist) Korn shell Job control (Unix) POSIX Rc Tom Duff Version 10 Unix Plan 9 from Bell Labs Plan 9 from User Space Bash GNU Almquist shell BSD licenses Computer Systems Research Group Debian Almquist shell Linux Unix-like