global (source code tagging system) GNU GLOBAL is a source code tagging system that works the same way across diverse environments (emacs, vi, less, bash, web browser, etc). You can locate objects in source files and move there easily. It is useful for hacking a large project containing many subdirectories, many #ifdef and many main() functions. It is similar to ctags or etags but is different from them at the point of independence of any editor. It runs on a UNIX(POSIX) compatible operating system like GNU and BSD.