Bash is the shell, or command language interpreter, for thegnuoperating system. Thename is an acronym for the ‘Bourne-Again SHell’, a pun on Stephen Bourne, the authorof the direct ancestor of the current Unix shellsh, which appeared in the Seventh Edition Bell Labs Research version of Unix.

Bash is largely compatible withshand incorporates useful features from the Korn shellkshand the C shellcsh. It is intended to be a conformant implementation of theieeeposixShell and Tools portion of theieee posixspecification (ieeeStandard 1003.1). Itoffers functional improvements overshfor both interactive and programming use.

While thegnuoperating system provides other shells, including a version ofcsh, Bashis the default shell. Like othergnusoftware, Bash is quite portable. It currently runs onnearly every version of Unix and a few other operating systems?independently-supportedports exist forms-dos,os/2, and Windows platforms. …