Start porting i18n from 5.2 to 6.0

Author: stevepiercy

docs/glossary.md

@@ -355,14 +355,31 @@ elementEditor
     A generic {term}`volto-slate` plugin architecture that can be used to create other editor interactions that follow the pattern of having a button that toggles a format (an inline element).
     It also creates a separate edit form for advanced customization of the data attached to the element.
 
+i18n
+internationalization
+    "i18n" is shorthand for "internationalization" (the letter "I", 18 letters, the letter "N").
+     It refers to the process of preparing a program so that it can be used in multiple languages without further altering the source code.
+      Plone is fully internationalized.
+
+gettext
+    UNIX standard software translation tool.
+    See https://www.gnu.org/software/gettext/.
+
+.po
+    The file format used by the gettext translation system.
+    See https://www.gnu.org/software/hello/manual/gettext/PO-Files.html.
+
+i18ndude
+    Support tool to create and update message catalogs from instrumented source code.
+
 WSGI
     The Web Server Gateway Interface (WSGI, pronounced _WIZ-ghee_) is a simple calling convention for web servers to forward requests to web applications or frameworks written in the Python programming language. 
 
 ZEO
-    [ZEO](https://zeo.readthedocs.io/) is a client-server storage for ZODB for sharing a single storage among many clients.
+    [ZEO](https://zeo.readthedocs.io/en/latest/) is a client-server storage for ZODB for sharing a single storage among many clients.
 
 ZODB
-    [A native object database for Python](https://zodb.org/).
+    [A native object database for Python](https://zodb.org/en/latest/).
 
 Zope
     [Zope](https://zope.readthedocs.io/) is a Python-based application server for building secure and highly scalable web applications.

docs/i18n/index.md

@@ -0,0 +1,39 @@
+---
+html_meta:
+  "description": "Internationalization (i18n) and localization (l10n) in Plone 6"
+  "property=og:description": "Internationalization (i18n) and localization (l10n) in Plone 6"
+  "property=og:title": "Internationalization (i18n)"
+  "keywords": "Plone, Internationalization, i18n, language, translation, localization"
+---
+
+(i18n-label)=
+
+# Internationalization (i18n)
+
+There are several layers involved in the processes that provide internationalization capabilities to Plone.
+They are separated into two parts:
+ 
+1.  Code-level elements.
+    This includes translations of the user interface and the display of the localization particularities, such as dates and decimal numbers.
+
+    -   Translating user interface text strings uses {term}`gettext`, as in the packages [`zope.i18n`](https://pypi.org/project/zope.i18n/) and [`zope.i18nmessageid`](https://pypi.org/project/zope.i18nmessageid/).
+    -   Adapting locale-specific settings, such as the time format, for a Plone site, as in the package [`plone.i18n`](https://pypi.org/project/plone.i18n/).
+
+2.  User-generated content.
+
+    -   For translating user-generated content, Plone uses the package [`plone.app.multilingual`](https://pypi.org/project/plone.app.multilingual/).
+
+
+(i18n-contents-label)=
+
+## Contents
+
+```{toctree}
+:maxdepth: 1
+
+internationalization
+language
+translating-content
+contribute-to-translations
+```
+

docs/index.md

@@ -25,6 +25,7 @@ volto/index
 plone.restapi/docs/source/index
 backend/index
 classic-ui/index
+i18n/index
 contributing/index
 ```