\section{Preprocesser symbols defined by wxWidgets}\label{cppconst}
-Here is the list of preprocessor symbols used in the wxWidgets source grouped
+These are preprocessor symbols used in the wxWidgets source, grouped
by category (and sorted by alphabetical order inside each category). All of
-these macros except for \texttt{wxUSE\_XXX} variety is defined if the
+these macros except for the \texttt{wxUSE\_XXX} variety is defined if the
corresponding condition is true and undefined if it isn't, so they should be
-always tested usin \texttt{#ifdef} and not \texttt{#if}.
-
+always tested using \texttt{#ifdef} and not \texttt{#if}.
\subsection{GUI system}\label{guisystemconst}
\begin{twocollist}\itemsep=0pt
\twocolitem{\_\_ALPHA\_\_}{DEC Alpha architecture}
\twocolitem{\_\_INTEL\_\_}{Intel i386 or compatible}
+\twocolitem{\_\_IA64\_\_}{Intel 64 bit architecture}
\twocolitem{\_\_POWERPC\_\_}{Motorola Power PC}
\end{twocollist}