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- So what is a shell script all about?

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Well, a shell script

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can be as simple as the number of commands

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that are sequentially executed.

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It's to automate your job

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and to make it a little bit easier for you

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to get things done.

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Scripts normally work with variables

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to make them react differently
in different environments.

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And when we talk about variables,

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think about the path
variable, for instance,

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which is a system variable,

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or an environment variable as we call it.

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And by referring to it,

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you can dynamically use values

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that are different in different locations

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and also in scripts conditional statements

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such as fur, if, case,
and while can be used

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to make it more flexible.

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So shell scripts are common

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as they are easy to learn and implement,

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and they are a part of the
Linux operating system.

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Also, a shell will always be available

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to interpret code from the shell script.

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If the scripts use internal commands only,

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they are very fast as
nothing needs to be loaded.

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Everything is already in
memory if it's a bash command,

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and there is no need to compile anything.

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There are also no modules to
be used in the bash script,

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and that makes them rather static.

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Also, bash shell scripts
are not item potent.

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So shell scripts are very nice,

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but in some cases, you might
want to use something else

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like Python or like Ansible

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if it's about configuration management.