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If you’ve been learning the <a set="yes" linkindex="8" href="http://en.wikipedia.org/wiki/Command_line_interface" title="Wikipedia Entry: Command line interface">command-line and you have the basics down (you should be, as the most effective way to use a computer is a combination of a GUI and command-line), the next step is to customize your environment.<div class="info_box">
<span class="info_box_title">Beginner’s Tip: ”command-line” and ”shell” are often used synonymously. In unix, technically speaking, the shell is what processes the command-line, but usually, they mean the same thing
The ability to fully customize your <a set="yes" linkindex="9" href="http://en.wikipedia.org/wiki/Unix_shell" title="Wikipedia Entry: Unix Shell (computing)">shell is one of the most powerful things about the command-line. It’s a dry subject, and mastering it won’t get you favors from the opposite sex (although it should), but it can be very useful.
There are many ways to customize your shell, but the first one you should learn is modifying your <a linkindex="10" href="http://en.wikipedia.org/wiki/bash" title="Wikipedia Entry: bash">Bash startup files (assuming your shell is Bash, which is the default in OS X, Linux, and many other unices).
When I first learned how to customize bash, I found an overwhelming amount of information and opinion, which made it difficult. This article is intended to give you the fundamental concepts so that you can create your own startup files, and understand how they work. To give you an example, I go through a subset of my own files, section by section.
Let’s install the example startup files<div class="info_box">
<span class="info_box_title">Beginner’s Tip: Directory and folder are synonymous. Often folder is used in Windows and OS X and directory is used in Linux, however even Linux represents a directory as a folder graphically