Added intro to design doc

designdoc.tex

@@ -55,12 +55,34 @@
 
 \section{Revision History}
 \begin{description}
+	\item[Revision 0.1] Nov 3, 2015: Added introduction
 	\item[Revision 0] Nov 2, 2015: Created document
 \end{description}
 
 \newpage
 
 \section{Introduction}
+The purpose of this document is to explain the design of the system for 
+PicPuzzle which is a Nonogram game. One of the main principles used to 
+design the system is information hiding. When decomposing the modules 
+into smaller modules, the idea is that each module should have its own 
+secret and should not expose it to the rest of the software. This 
+creates modular code that is easy to modify. 
+
+A main architectural pattern followed is a modification of the MVC 
+(Model-View-Controller) pattern. This modified MVC is called MVP 
+(Model-View-Presenter). In the pattern a model represents the data 
+structures. A view is a passive entity that displays data and passes 
+user events to the presenter. The presenter acts on events and the 
+model. Also, the presenter formats data to be displayed on the view. 
+
+Other documents that relate to this one are the Software Requirements 
+Specification (SRS) and the Module Interface Specification (MIS). The 
+SRS contains the requirements for the system and those requirements are 
+implemented by the modules specified in this document. The MIS contains 
+an overview of each module and its publicly accessible programs. This 
+relates because this is a more detailed description of each module 
+described in this document. 
 
 \section{Anticipated and Unlikely Changes}