linux_introduction/readme.md

# Hello world

Welcome!

Essential: introduction to linux
=================

* [Introduction to Linux](./essential/introduction_to_linux.md#introduction-to-linux)
   * [Where does Linux originate from?](./essential/introduction_to_linux.md#where-does-linux-originate-from)
   * [Who is behind this project?](./essential/introduction_to_linux.md#who-is-behind-this-project)
   * [What is the deal with 'GNU-slash-Linux'?](./essential/introduction_to_linux.md#what-is-the-deal-with-gnu-slash-linux)
   * [Where can you <em>get</em> some Linux?](./essential/introduction_to_linux.md#where-can-you-get-some-linux)
   * [Debian](./essential/introduction_to_linux.md#debian)
* [How to create a virtual machine](./essential/introduction_to_linux.md#how-to-create-a-virtual-machine)
* [Breakdown of the Debian installation](./essential/introduction_to_linux.md#breakdown-of-the-debian-installation)
* [Exercise](./essential/introduction_to_linux.md#exercise)
* [Quick look at an idle system](./essential/introduction_to_linux.md#quick-look-at-an-idle-system)
* [Package managers](./essential/introduction_to_linux.md#package-managers)
   * [Graphical installation](./essential/introduction_to_linux.md#graphical-installation)
   * [Command line installation](./essential/introduction_to_linux.md#command-line-installation)
   * [Adding a secondary desktop environment](./essential/introduction_to_linux.md#adding-a-secondary-desktop-environment)
* [Changing the runlevel](./essential/introduction_to_linux.md#changing-the-runlevel)
* [Exercise](./essential/introduction_to_linux.md#exercise-1)
* [Guest additions](./essential/introduction_to_linux.md#guest-additions)

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Essential: introduction to the commandline
=================

* [Introduction to the command line](./essential/introduction_to_the_commandline.md#introduction-to-the-command-line)
   * [Compiled vs interpreted](./essential/introduction_to_the_commandline.md#compiled-vs-interpreted)
   * [Note on file extensions](./essential/introduction_to_the_commandline.md#note-on-file-extensions)
* [More about paths](./essential/introduction_to_the_commandline.md#more-about-paths)
   * [Absolute and relative paths](./essential/introduction_to_the_commandline.md#absolute-and-relative-paths)
   * [root and  / and /root are not the same thing](./essential/introduction_to_the_commandline.md#root-and---and-root-are-not-the-same-thing)
* [Exercise](./essential/introduction_to_the_commandline.md#exercise)
* [A pit stop to review what we've learned so far](./essential/introduction_to_the_commandline.md#a-pit-stop-to-review-what-weve-learned-so-far)
* [Arguments and flags](./essential/introduction_to_the_commandline.md#arguments-and-flags)
* [Getting help](./essential/introduction_to_the_commandline.md#getting-help)
   * [Options](./essential/introduction_to_the_commandline.md#options)
   * [Manuals](./essential/introduction_to_the_commandline.md#manuals)
   * [Exercise](./essential/introduction_to_the_commandline.md#exercise-1)
* [Creating, modifying and deleting](./essential/introduction_to_the_commandline.md#creating-modifying-and-deleting)
   * [Directories](./essential/introduction_to_the_commandline.md#directories)
   * [Files](./essential/introduction_to_the_commandline.md#files)
   * [Links](./essential/introduction_to_the_commandline.md#links)
* [Editors](./essential/introduction_to_the_commandline.md#editors)
   * [nano](./essential/introduction_to_the_commandline.md#nano)
      * [Exercise](./essential/introduction_to_the_commandline.md#exercise-2)
   * [vi and vim](./essential/introduction_to_the_commandline.md#vi-and-vim)
      * [Exercise](./essential/introduction_to_the_commandline.md#exercise-3)
* [Opening or peaking into files](./essential/introduction_to_the_commandline.md#opening-or-peaking-into-files)
* [Exercise](./essential/introduction_to_the_commandline.md#exercise-4)
* [Finding stuff](./essential/introduction_to_the_commandline.md#finding-stuff)
   * [Finding files](./essential/introduction_to_the_commandline.md#finding-files)
      * [The easy way](./essential/introduction_to_the_commandline.md#the-easy-way)
      * [The hard way](./essential/introduction_to_the_commandline.md#the-hard-way)
* [Exercise](./essential/introduction_to_the_commandline.md#exercise-5)
* [Searching inside files](./essential/introduction_to_the_commandline.md#searching-inside-files)
   * [Wildcards and regular expressions](./essential/introduction_to_the_commandline.md#wildcards-and-regular-expressions)
      * [Wildcards](./essential/introduction_to_the_commandline.md#wildcards)
* [Exercise](./essential/introduction_to_the_commandline.md#exercise-6)
* [Exercise](./essential/introduction_to_the_commandline.md#exercise-7)
      * [Regular expressions](./essential/introduction_to_the_commandline.md#regular-expressions)
* [Pipes and redirects](./essential/introduction_to_the_commandline.md#pipes-and-redirects)
   * [Redirecting](./essential/introduction_to_the_commandline.md#redirecting)
   * [Piping](./essential/introduction_to_the_commandline.md#piping)
* [Text manipulation](./essential/introduction_to_the_commandline.md#text-manipulation)
* [Ideas](./essential/introduction_to_the_commandline.md#ideas)

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Essential: introduction to administration
=================

* [Users](./essential/introduction_to_administration.md#users)
   * [Adding and removing users](./essential/introduction_to_administration.md#adding-and-removing-users)
      * [GNOME](./essential/introduction_to_administration.md#gnome)
      * [command line](./essential/introduction_to_administration.md#command-line)
   * [Switching user](./essential/introduction_to_administration.md#switching-user)
   * [Groups](./essential/introduction_to_administration.md#groups)
* [Permissions](./essential/introduction_to_administration.md#permissions)
   * [Octal number system](./essential/introduction_to_administration.md#octal-number-system)
   * [Changing ownership](./essential/introduction_to_administration.md#changing-ownership)
   * [umask](./essential/introduction_to_administration.md#umask)
   * [Essential programs](./essential/introduction_to_administration.md#essential-programs)
* [Remote control of a server](./essential/introduction_to_administration.md#remote-control-of-a-server)
   * [History](./essential/introduction_to_administration.md#history)
   * [SSH and SFTP](./essential/introduction_to_administration.md#ssh-and-sftp)
* [Bandit](./essential/introduction_to_administration.md#bandit)

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Advanced: learning bash scripting
=================

* [bash](./advanced/learning_bash_scripting.md#bash)
* [Using variables to store the output of command](./advanced/learning_bash_scripting.md#using-variables-to-store-the-output-of-command)
* [Coding challenge - Output system stats](./advanced/learning_bash_scripting.md#coding-challenge---output-system-stats)
* [Getting input into the script](./advanced/learning_bash_scripting.md#getting-input-into-the-script)
   * [With read](./advanced/learning_bash_scripting.md#with-read)
* [Coding challenge - Secret input](./advanced/learning_bash_scripting.md#coding-challenge---secret-input)
      * [read multiple variables](./advanced/learning_bash_scripting.md#read-multiple-variables)
   * [With command line arguments](./advanced/learning_bash_scripting.md#with-command-line-arguments)
   * [From a file](./advanced/learning_bash_scripting.md#from-a-file)
   * [From a pipe](./advanced/learning_bash_scripting.md#from-a-pipe)
* [Coding Challenge - output the exact output below](./advanced/learning_bash_scripting.md#coding-challenge---output-the-exact-output-below)
* [More math!](./advanced/learning_bash_scripting.md#more-math)
   * [The let keyword](./advanced/learning_bash_scripting.md#the-let-keyword)
   * [The expr keyword](./advanced/learning_bash_scripting.md#the-expr-keyword)
   * [Double parenthesis](./advanced/learning_bash_scripting.md#double-parenthesis)
   * [Variable length](./advanced/learning_bash_scripting.md#variable-length)
* [If Statements - How to make decisions within your Bash script.](./advanced/learning_bash_scripting.md#if-statements---how-to-make-decisions-within-your-bash-script)
   * [How does it work behind the scenes?](./advanced/learning_bash_scripting.md#how-does-it-work-behind-the-scenes)
   * [Nested if statements](./advanced/learning_bash_scripting.md#nested-if-statements)
* [Coding challenge - File information](./advanced/learning_bash_scripting.md#coding-challenge---file-information)
   * [A <em>modern</em> version of test](./advanced/learning_bash_scripting.md#a-modern-version-of-test)
      * [[[  ]]](./advanced/learning_bash_scripting.md#--)
      * [((  ))](./advanced/learning_bash_scripting.md#---1)
      * [&amp;&amp; and  ||](./advanced/learning_bash_scripting.md#-and--)
* [Loops - A variety of ways to perform repetitive tasks.](./advanced/learning_bash_scripting.md#loops---a-variety-of-ways-to-perform-repetitive-tasks)
* [Functions - Reuse code to make life easier.](./advanced/learning_bash_scripting.md#functions---reuse-code-to-make-life-easier)
* [User Interface - Make your scripts user friendly.](./advanced/learning_bash_scripting.md#user-interface---make-your-scripts-user-friendly)
   * [Python](./advanced/learning_bash_scripting.md#python)
   * [Vim as an IDE](./advanced/learning_bash_scripting.md#vim-as-an-ide)

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