Add additional resources to the README

Author: Tania Allard

README.md

@@ -30,3 +30,8 @@ In order to access this follow the next instructions:
 ![clone](./assets/clone_gitkraken.gif)
 
 You should have now a copy of the main repository!!!! 🤓🎉🎈
+
+
+## Additional materials
+- [GitHub super useful cheatsheet](https://services.github.com/on-demand/downloads/github-git-cheat-sheet.pdf)
+- [Mini terminal / command line tutorial](./terminal.md)

terminal.md

@@ -0,0 +1,95 @@
+# Basic use of the command line
+
+Learning to use the command line is essential for advanced programming, but it can also
+improve your day to day tasks.
+You can access your entire computer via the command line and do everything you can normally do
+using the Graphical User Interface... and more.
+
+This (mini)tutorial will guide you through the very basics of using
+the command line.
+
+When you launch a terminal, the default path/location is your home directory, however
+if at any point you are unsure which folder you are "in" (which is your working
+directory) you only need to type the command `pwd`.
+
+## Understanding the syntax
+When you open the terminal you might see a *prompt* similar to:
+
+```
+username@computer ~ $
+```
+
+- The `~` character is typically shorthand for your *home directory*.  Here you being told that your *present working directory* is your home directory.
+- The `$` (Ready) indicates that the prompt is ready to accept your command; the `$` is just there, you do not need to type it.
+
+## Clear
+At some point you might end up with your terminal full of lines. By typing the command `clear` you can clear the terminal screen.
+
+## Listing the Directory contents
+If within a directory you want to see its content you can use the `ls` command.
+
+If you need more detailed information on the contents (e.g. access permissions,
+date the file was last modified, etc.) you can use the command `ls -l`.
+
+## Moving between directories
+To change your working directory you need to use the `cd` command (change directory), followed by the *pathname* of the directory you want to move into e.g:
+
+```bash
+cd /HelloWorld/src/
+```
+
+If you do not specify a pathname and just type `cd`, which will take you back to your home directory.
+
+If you want to go to the previous directory (or a directory closer to the root) you can type `cd ..`. This will take you back one directory at a time.
+
+If you are trying to move to a directory that has spaces in the path you need to use "" to preserve the spaces: `cd "Mini tutorial"`
+
+## Creating directories
+So far we have covered how to move between existing directories, but we can just as well create directories using the command line:
+`mkdir HelloWorld`
+If you want to create a folder within the HelloWorld directory you just created you can do it by typing `mkdir HelloWorld/data` without the need to change directories first.
+
+If you need to create a multiple embedded directories, instead of creating one by one you can use the `mkdir` option `-p` which will create the parent directories i.e.
+
+```bash
+mkdir -p Helloworld/data/myproject/test1/
+```
+
+## Creating files
+You can create empty files using the `touch` command, for example `touch project.scala`. For this you need to be into the directory you want the file to be created, otherwise you need to specify the full path of the file:
+
+`touch HelloWorld/data/one.txt`
+
+You can even create multiple files at a time `touch one.txt two.txt`
+
+
+## Deleting files
+To permanently delete files you can use the `rm` command e.g.
+
+```bash
+rm one.txt
+```
+
+Or even delete various files at a time
+
+```bash
+rm one.txt two.txt
+```
+
+To delete *empty* directories:
+
+```bash
+rmdir dir1/an-empty-dir
+```
+
+To recursively delete directories (delete non-empty directories and their contents):
+
+```bash
+rm -r dir1/dir_with_stuff_in
+```
+
+## Copying files
+You can copy files between directories by using `cp source destination` indicating the path of the file and then the path where you want the copy to be created.
+
+## But it is too much typing...
+We've got you covered! Let's say you want to go to your data directory. You can start use the autocomplete function you can start typing `cd HelloWorld/da` and then press the **Tab** key on your keyboard and the prompt will... well autocomplete the path for you.