wxWidgets library is divided into libraries briefly described below. This diagram show dependencies between them:
wxBase
Every wxWidgets application must link against this library. It contains mandatory classes that any wxWidgets code depends on (e.g. wxString) and portability classes that abstract differences between platforms. wxBase can be used to develop console mode applications, it does not require any GUI libraries or running X Window System on Unix.
wxNet
Classes for network access:
wxXML
This library contains simple classes for parsing XML documents. Note that their API will change in the future and backward compatibility will not be preserved. Use of this library in your applications is not recommended, it is only meant for use by XML resources system. Future versions of wxWidgets will contain new XML handling classes with DOM-like API. Requires wxBase.
wxCore
Basic GUI classes such as GDI classes or controls are in this library. All wxWidgets GUI applications must link against this library, only console mode applications don't.
wxAdvanced
More advanced or rarely used GUI classes:
Requires wxCore and wxBase.
wxGL
This library contains wxGLCanvas class for integrating OpenGL library with wxWidgets. Unlike all others, this library is not part of the monolithic library, it is always built as separate library. Requires wxCore and wxBase.
wxHTML
Simple HTML renderer and other HTML rendering classes are contained in this library, as well as wxHtmlHelpController, wxBestHelpController and wxHtmlListBox. Requires wxCore and wxBase.
wxODBC
Database classes. Requires wxBase.
wxDbGrid
wxDbGridTableBase class which combines wxGrid and wxDbTable. Requires wxODBC and wxAdvanced.
wxXRC
This library contains wxXmlResource class that provides access to XML resource files in XRC format. Requires wxXML, wxCore, wxAdvanced and wxHTML.