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An operating system software user interface, whose primary purpose is to launch other programs and control their interactions; the user's command interpreter. Shell is a way to separate the internal complexity of the implementation of the command from the user. The internals can change while the user experience/interface remains the same.
“Bash”这个名字是一个缩写,代表“Bourne-again shell”(伯恩重现的Shell),这本身就是一个双关语,一方面指斯蒂芬·伯恩设计的早期Unix Shell“Bourne shell”(伯恩Shell),另一方面也暗指基督教“重生”的概念。 其中,“Bourne-again shell” 里的"shell"指的是一个外壳程序或命令解释器,它让用户可以通过命令来控制电脑,而不需要了解电脑内部复杂的运作方式。














