+The Basic Elements
+The 2i2c computing service is an implementation of the Jupyter Hub on
+dedicated hardware accessible over the web. There is a great deal of information
+about Jupyter available at the Jupyter project site, http://jupyter.org/
+There are four key concepts to master:
+
+This chapter discusses all four.
+
+Using the Hub
+You get to the Hub by logging into the showcase.2i2c.cloud
+service and clicking the button to “Start My Server.”
+The Hub is a page that lists all your files and folders. It looks like this:
+
+As you can see, the Hub looks a lot like the list of files and folders you would
+see in the Finder on MacOS, or in the File Explorer in Windows.
+At the top right corner of this front page is a “Control Panel” that lets you
+access your Jupyter server, to turn it on or off. Also is the logout button, to
+end your session.
+The main body is the list of folders and files that you have on your server.
+Click on a file or folder to open it. Use the checkbox on the left to select a
+file, then do something with it. For instance, you can choose to rename it, copy
+it, stop it from running, or delete it.
+It is a good idea to create folders at the top level, to organize your work into
+usable spaces. It turns out it is hard to move a file once it is created. (More
+on this below.) So you should start by organizing your folders and files at the
+top level.
+Near the top right, you see the upload button, which allows you to upload a file
+from your computer onto the Jupyter Hub. You can upload any file, including any
+data files or image files you might wish to analyse.
+Also near the top right is the “New” button, which allows you to create a new
+folder or file. You can make text files, notebook files in Python, Julia or R,
+or open a Unix terminal window.
+
+
+Moving files between folders
+It’s not documented, but there is a way to move files and folders in and out of
+various folders directly from the Hub.
+Select a file listed in the Hub by clicking on the square box at the left of the
+file’s name. You are then given the option to “rename” the file. Click on the
+rename button, and then enter one of the following:
+
+newname
– to give the file the new name
+../oldname
– to move the file up and out of the current folder, into the
+previous forder
+foldername/oldname
– to move the file into the folder called “foldername.”
+This folder should already exist (because you created it earlier with a “new
+folder” command).
+
+These renaming methods also work to move folders and their contents.
+To move across several branches in the directory tree, you need to know the full
+path name of your files and where they are to go. This means you need to find
+out the name of your root tree structure. A fast way to do this is to use the
+magic command %cd
in a notebook.
+Open a notebook, click on an empty cell, and type %cd
, hit shift-return. It
+will return the director root name. Typically something like /home/username
or
+/home/usernumber
.
+You can now use this to move a file into any folder. Just rename the file
+something like /home/username/folderA/filename
. (the folderA better exist
+already, for you to move something into this.)
+
+
+Using Notebooks
+From the Hub, you can click on a Notebook (a files with the suffix .ipynb) or
+create a new one with the “New” button. You need to pick a computing language
+(Python, Julia or R) when you create a new Notebook; for now, just choose
+Python 3.
+The Notebook will look something like this.
+
+At the top is the name of the notebook (in this case, “Untitled”). You can click
+on that name and edit it to whatever you like.
+Just under the title is the menu bar, which allows you to do many things with
+the Notebook, including saving it, downloading it to your own computer, editing
+it, inserting new cells, and so on.
+There is also an icon bar of menu short cuts. All of them are pretty obvious.
+Below the menu controls is the Notebook content, which consists of a sequence of
+cells. Each cell can contain Markdown text or computer code. You select which
+kind of content for that cell from the little icon in the icon bar at the top.
+In the example illustrated here, the first cell is just text. It says “This is
+an example of a Notebook.” The second cell is Markdown text, including a math
+formula in LaTeX format. It starts “Here is an example of some math…”
+The third cell shows the math formula as a real math formula, with an integral
+sign and all. The math is just typed in (like in the second cell), and then you
+hit “shift-return” on the keyboard to typeset the math.
+The final few cells show some code, that loads in some plotting tools and makes
+a simple plot.
+
+
+Pretty Text and Math (Markdown Language)
+One great feature of the Jupyter Notebooks is that they can contain formatted
+text, and mathematics, using the Markdown language.
+Markdown is a rich language: a quick introduction to it is available here:
+https://guides.github.com/features/mastering-markdown/
+Some quick points.
+
+Editting and typesetting
+You simply type your text and Markdown symbols into a cell, and hit
+“shift-return” to typeset the cell into pretty text (and math). Click on the
+cell again to undo the typesetting, so you can edit and fix your text. Make
+sure, of course, that you have marked the cell as “Markdown” and not “Code.”
+
+
+
+Emphasis
+Add emphasis by surrounding text with asterix or underscores.
+* italics * and ** bold **: Italics and bold
+
+
+Lists
+Type this:
+* Apple
+* Orange
+* Pear
+to get a list like this:
+
+
+
+Web links
+Type this: [GitHub](github)
+to get a clickable link GitHub
+
+
+Mathematics
+Use the dollar sign $ to indicate the start and end of TeX code for your math.
+Here is a basic integral: $\int \cos(x) dx = \sin(x)$
+
+
+Here is a basic integral: $\(\int \cos(x) dx =
+\sin(x)\)$
+
+
+Images
+Here is some code to embed an image from the web:
+![Image of Yaktocat](https://octodex.github.com/images/yaktocat.png)
+
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