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2008-06-11 11:10:13
Just like people know different languages and dialects, your UNIX system will usually offer a variety of shell types:
sh or Bourne Shell: the original shell still used on UNIX systems and in UNIX-related environments. This is the basic shell, a small program with few features. While this is not the standard shell, it is still available on every Linux system for compatibility with UNIX programs.
bash or Bourne Again shell: the standard GNU shell, intuitive and flexible. Probably most advisable for beginning users while being at the same time a powerful tool for the advanced and professional user. On Linux, bash is the standard shell for common users. This shell is a so-called superset of the Bourne shell, a set of add-ons and plug-ins. This means that the Bourne Again shell is compatible with the Bourne shell: commands that work in sh, also work in bash. However, the reverse is not always the case. All examples and exercises in this book use bash.
csh or C shell: the syntax of this shell resembles that of the C programming language. Sometimes asked for by programmers.
tcsh or Turbo C shell: a superset of the common C shell, enhancing user-friendliness and speed.
ksh or the Korn shell: sometimes appreciated by people with a UNIX background. A superset of the Bourne shell; with standard configuration a nightmare for beginning users.
