+\subsection{Hardware type}\label{hardwareconst}
+
+Combination of these symbols with GUI symbols describes real hardware
+(like \_\_PDA\_\_ $&&$ \_\_WXWINCE\_\_ $==$ PocketPC devices).
+
+\begin{twocollist}\itemsep=0pt
+\twocolitem{\_\_SMARTPHONE\_\_}{Mobile devices with dialog capability through
+phone buttons and small display}
+\twocolitem{\_\_PDA\_\_}{Personal digital assistant usually with touch screen and
+middle sized screen}
+\twocolitem{\_\_HANDHELD\_\_}{Small enough but powerful computer}
+\end{twocollist}
+
+\subsection{Compilers}\label{compilerconst}