Add glossary

docs/what_is_jupyter.rst

@@ -15,6 +15,9 @@ Notebooks documents are both human-readable documents containing the analysis
 description and the results (figures, tables, etc..) and executable documents
 that can be run to perform a data analysis.
 
+Links
+-----
+
 Official Pages:
 
 - `Project Jupyter <https://jupyter.org/>`__
@@ -23,3 +26,60 @@ Official Pages:
 Quick introductions:
 
 - `What is the IPython Notebook? <http://nbviewer.ipython.org/github/jupyter/strata-sv-2015-tutorial/blob/master/00%20-%20Introduction.ipynb>`__
+
+Quick Glossary
+--------------
+
+.. _notebook_app:
+
+*Jupyter Notebook App*
+~~~~~~~~~~~~~~~~~~~~~~
+
+The *Jupyter Notebook App* is a server application that allows 
+operating on notebook documents (open, close, run, etc...).
+In this guide the *Jupyter Notebook App* is run on a local desktop 
+and does not require any internet access.
+In addition to displaying/editing/running notebook documents, 
+the *Jupyter Notebook App* has a "Dashboard" (:ref:`dashboard`)
+that is a sort of control panel showing local files and allowing to
+open notebook documents or shut-downing their :ref:`*kernels* <kernel>`.
+
+
+.. _kernel:
+
+*kernel*
+~~~~~~~~
+
+A notebook kernel, or simply a *kernel*, is a "computational engine"
+that executes the code contained in a notebook document.
+In this guide we always refer to a specific kernel called *ipython kernel* 
+that executes python code. 
+Kernels for many other languages exists, the *ipython kernel* is the one
+for the python language.
+
+When opening a notebook document the associated *kernel* is automatically launched.
+When the notebook is *executed* (either cell-by-cell or with menu *Cell -> Run All*)
+the *kernel* performs the computation and produces the results.
+Depending on the type of computations, the *kernel* may consume significant
+CPU and RAM. Note that the RAM is not released until the kernel is shut-down.
+
+To shut-down the kernel **is not sufficient to close the tab** where the notebook is.
+You have to use the menu *File -> Close and Halt*. Alternatively, the *Notebook Dashboard*
+highlights notebooks with running kernels and allows to shut them dowm.
+
+
+.. _dashboard:
+
+*Notebook Dashboard*
+~~~~~~~~~~~~~~~~~~~~
+
+The *Notebook Dashboard* is the component of the *Jupyter Notebook App* that is
+first shown when the :ref:`notebook_app` is launched.
+
+Mainly, the *Notebook Dashboard* is used to open notebook documents, and manage
+the running kernels (visulaize and shutdown).
+
+The *Notebook Dashboard* has other features similar to a file manager, namely
+navigating folders and renaming/deleting files.
+
+