\twocolitem{\_\_WIN16\_\_}{Win16 API (not supported since wxWindows 2.6)}
\twocolitem{\_\_WIN32\_\_}{Win32 API}
\twocolitem{\_\_WIN95\_\_}{Windows 95 or NT 4.0 and above system (not NT 3.5x)}
+\twocolitem{\_\_WXBASE\_\_}{Only wxBase, no GUI features}
\twocolitem{\_\_WXGTK\_\_}{GTK}
\twocolitem{\_\_WXGTK12\_\_}{GTK 1.2 or higher}
\twocolitem{\_\_WXGTK20\_\_}{GTK 2.0 or higher}
\begin{twocollist}\itemsep=0pt
\twocolitem{\_\_WXWINDOWS\_\_}{always defined in wxWindows applications, see
also \helpref{wxCHECK\_VERSION}{wxcheckversion}}
-\twocolitem{\_\_WXBASE\_\_}{only used by wxWindows internally (defined when
-building wxBase code, either as a standalone library or as part of the
-monolithis wxWindows library, not defined when building GUI library only)}
\twocolitem{\_\_WXDEBUG\_\_}{defined in debug mode, undefined in release mode}
\twocolitem{wxUSE\_XXX}{if defined as $1$, feature XXX is active
(the symbols of this form are always defined, use \#if and not \#ifdef to test
for them)}
+\twocolitem{wxUSE\_GUI}{this particular feature test macro is defined to $1$
+when compiling or using the library with the GUI features activated, if it is
+defined as $0$, only wxBase is available.}
+\twocolitem{wxUSE\_BASE}{only used by wxWindows internally (defined as $1$ when
+building wxBase code, either as a standalone library or as part of the
+monolithic wxWindows library, defined as $0$ when building GUI library only)}
\end{twocollist}