desired outcome. At a high level, the subject areas describe:
* xref:concepts.adoc[Concepts] and introduction for newcomers.
+* xref:installation:index.adoc[Installing] and xref:installation:upgrade.adoc[upgrading] FreeRADIUS.
* The syntax of the xref:unlang:index.adoc[unlang] processing language.
* The xref:raddb:index.adoc[configuration files] located in `/etc/raddb/`, or `/etc/freeradius/`
* Various xref:howto:index.adoc[how-to] guides.
-* xref:installation:upgrade.adoc[Upgrading] from a previous version of FreeRADIUS.
* xref:developers:index.adoc[Developer documentation].
This organization means that for example, the `ldap` module will have