Merge pull request #2275 from jf205/sd-4017

Learn CodeQL docs: add short note about new terminology

docs/language/learn-ql/index.rst

@@ -9,6 +9,18 @@ Here, you can query open source projects directly, without having to download Co
 
 CodeQL is based on a powerful query language called QL. The following topics help you understand QL in general, as well as how to use it when analyzing code with CodeQL.
 
+.. pull-quote::
+
+   Important 
+
+   If you've previously used QL, you may notice slight changes in terms we use to describe some important concepts. For more information, see our note about :doc:`Recent terminology changes <terminology-note>`.
+
+.. toctree::
+   :hidden:
+
+   terminology-note
+   
+
 .. _getting-started:
 
 Getting started
@@ -86,4 +98,4 @@ Search
 
 .. * :ref:`genindex` remove index for the time being as we currently have no tags
 
-* :ref:`search`
+* :ref:`search`

docs/language/learn-ql/terminology-note.rst

@@ -0,0 +1,27 @@
+Recent terminology changes
+===========================
+
+We recently started using new terminology to make it clearer to users what our products do. 
+This note gives some information about what has changed.
+
+CodeQL
+------
+
+CodeQL is the code analysis platform formerly known as QL. 
+CodeQL treats code as data, and CodeQL analysis is based on running queries against your code to check for errors and find bugs and vulnerabilities.
+The CodeQL product includes the tools, scripts, queries, and libraries used in CodeQL analysis. 
+
+QL
+---
+
+Previously we used the term QL to refer to the whole code analysis platform, which has been renamed CodeQL. 
+The name QL now only refers to the query language that powers CodeQL analysis.
+
+The CodeQL queries and libraries used to analyze source code are written in QL.
+These queries and libraries are open source, and can be found in the `CodeQL repository <https://github.com/semmle/ql>`__.
+QL is a general-purpose, object-oriented language that can be used to query any kind of data. 
+
+CodeQL databases
+----------------
+
+QL snapshots have been renamed CodeQL databases. :doc:`CodeQL databases <database>` contain relational data created and analyzed using CodeQL. They are the equivalent of QL snapshots, but have been optimized for use with the CodeQL tools.