diff --git a/devcpp/photon.dev b/devcpp/photon.dev
index 4748da9..e431e25 100644
--- a/devcpp/photon.dev
+++ b/devcpp/photon.dev
@@ -1,7 +1,7 @@
 [Project]
 FileName=photon.dev
 Name=photon
-UnitCount=17
+UnitCount=20
 Type=2
 Ver=1
 ObjFiles=
@@ -20,7 +20,7 @@ ObjectOutput=..\devcpp
 OverrideOutput=1
 OverrideOutputName=libphoton.a
 HostApplication=
-Folders=external,external/include,external/src,include,include/util,src,src/util
+Folders=include,include/util,src,src/util
 CommandLine=
 UseCustomMakefile=0
 CustomMakefile=
@@ -217,3 +217,33 @@ Priority=1000
 OverrideBuildCmd=0
 BuildCmd=
 
+[Unit18]
+FileName=..\include\Application.h
+CompileCpp=1
+Folder=include
+Compile=1
+Link=1
+Priority=1000
+OverrideBuildCmd=0
+BuildCmd=
+
+[Unit19]
+FileName=..\src\Application.cpp
+CompileCpp=1
+Folder=src
+Compile=1
+Link=1
+Priority=1000
+OverrideBuildCmd=0
+BuildCmd=
+
+[Unit20]
+FileName=..\include\entrypoint.h
+CompileCpp=1
+Folder=include
+Compile=1
+Link=1
+Priority=1000
+OverrideBuildCmd=0
+BuildCmd=
+
diff --git a/include/Log.h b/include/Log.h
index 47ff0fc..dbb61b3 100644
--- a/include/Log.h
+++ b/include/Log.h
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: Log.h,v 1.2 2005/02/04 08:11:54 cozman Exp $
+//  $Id: Log.h,v 1.3 2005/02/07 01:48:26 cozman Exp $
 //
 // Revisions:
 //  $Log: Log.h,v $
+//  Revision 1.3  2005/02/07 01:48:26  cozman
+//  string references
+//
 //  Revision 1.2  2005/02/04 08:11:54  cozman
 //  switched Log to shared_ptrs and added extra flushes
 //
@@ -30,8 +33,8 @@ namespace photon
 { 
 
 // Class: Log
-//  Log class for photon, Log passes all messages to any attached sinks, which
-//  can then take care of any output which is desired.
+//  Log class for photon, Log passes all messages to any attached <LogSinks>,
+//  which can then take care of any output which is desired.
 class Log
 {
 
@@ -55,7 +58,7 @@ public:
     //
     //  Parameters:
     //      sinkName - Name of sink to remove.
-    void removeSink(std::string sinkName);
+    void removeSink(const std::string& sinkName);
 
     // Function: removeSink
     //  Remove a sink from the log.
diff --git a/include/LogSink.h b/include/LogSink.h
index 59dc05f..b8473f4 100644
--- a/include/LogSink.h
+++ b/include/LogSink.h
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: LogSink.h,v 1.4 2005/02/05 03:01:03 cozman Exp $
+//  $Id: LogSink.h,v 1.5 2005/02/07 01:48:26 cozman Exp $
 //
 // Revisions:
 //  $Log: LogSink.h,v $
+//  Revision 1.5  2005/02/07 01:48:26  cozman
+//  string references
+//
 //  Revision 1.4  2005/02/05 03:01:03  cozman
 //  removed getStream() (useless)
 //
@@ -77,7 +80,7 @@ public:
     //
     // Parameters:
     //  name_ - Name of LogSink, every LogSink should have a unique name.
-    LogSink(std::string name);
+    LogSink(const std::string& name);
 
     // Function: ~LogSink
     //  Virtual destructor, available to make inheritance safe.
@@ -93,7 +96,7 @@ public:
     // Parameters:
     //  level - <LogLevel> of log event.
     //  msg - String describing log message.
-    virtual void writeMessage(LogLevel level, std::string msg)=0;
+    virtual void writeMessage(LogLevel level, const std::string& msg)=0;
 
 // Group: Accessors
 public:
@@ -129,10 +132,10 @@ typedef shared_ptr<LogSink> LogSinkPtr;
 class ConsoleSink : public LogSink
 {
 public:
-    ConsoleSink(std::string name);
+    ConsoleSink(const std::string& name);
     virtual ~ConsoleSink();
     
-    virtual void writeMessage(LogLevel level, std::string msg);
+    virtual void writeMessage(LogLevel level, const std::string& msg);
 };
 
 // Class: TextSink
@@ -146,10 +149,10 @@ public:
 class TextSink : public LogSink
 {
 public:
-    TextSink(std::string name);
+    TextSink(const std::string& name);
     virtual ~TextSink();
     
-    virtual void writeMessage(LogLevel level, std::string msg);
+    virtual void writeMessage(LogLevel level, const std::string& msg);
 private:
     std::ofstream out_;
 };
@@ -165,10 +168,10 @@ private:
 class HTMLSink : public LogSink
 {
 public:
-    HTMLSink(std::string name);
+    HTMLSink(const std::string& name);
     virtual ~HTMLSink();
     
-    virtual void writeMessage(LogLevel level, std::string msg);
+    virtual void writeMessage(LogLevel level, const std::string& msg);
 private:
     std::ofstream out_;
 };
diff --git a/include/exceptions.h b/include/exceptions.h
index ad23ff9..a3f4ecd 100644
--- a/include/exceptions.h
+++ b/include/exceptions.h
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: exceptions.h,v 1.4 2005/02/06 21:28:47 cozman Exp $
+//  $Id: exceptions.h,v 1.5 2005/02/07 01:48:26 cozman Exp $
 //
 // Revisions:
 //  $Log: exceptions.h,v $
+//  Revision 1.5  2005/02/07 01:48:26  cozman
+//  string references
+//
 //  Revision 1.4  2005/02/06 21:28:47  cozman
 //  removed require
 //
@@ -59,8 +62,8 @@ public:
     //  description - description of why exception was thrown [default: empty]
     //  file - name of file where exception was thrown [default: empty]
     //  line - line in file where exception was thrown [default: 0]
-    Throwable(std::string description = std::string(),
-                std::string file = std::string(),
+    Throwable(const std::string& description = std::string(),
+                const std::string& file = std::string(),
                 uint line=0) throw();
     virtual ~Throwable() throw()=0;
 
@@ -97,8 +100,8 @@ private:
 class Exception : public Throwable
 {
 public:
-    Exception(std::string description = std::string(),
-                std::string file = std::string(),
+    Exception(const std::string& description = std::string(),
+                const std::string& file = std::string(),
                 uint line=0) throw();
     friend std::ostream& operator<<(std::ostream& os,
                                     const Exception& rhs);
@@ -116,8 +119,8 @@ public:
 class ArgumentException : public Exception
 {
 public:
-    ArgumentException(std::string description = std::string(),
-                        std::string file = std::string(),
+    ArgumentException(const std::string& description = std::string(),
+                        const std::string& file = std::string(),
                         uint line=0) throw();
     friend std::ostream& operator<<(std::ostream& os,
                                     const ArgumentException& rhs);
@@ -134,8 +137,8 @@ public:
 class PreconditionException : public Exception
 {
 public:
-    PreconditionException(std::string description = std::string(),
-                            std::string file = std::string(),
+    PreconditionException(const std::string& description = std::string(),
+                            const std::string& file = std::string(),
                             uint line=0) throw();
     friend std::ostream& operator<<(std::ostream& os,
                                     const PreconditionException& rhs);
@@ -154,8 +157,8 @@ class RangeException : public Exception
 {
 public:
     RangeException() throw();
-    RangeException(std::string description = std::string(),
-                    std::string file = std::string(),
+    RangeException(const std::string& description = std::string(),
+                    const std::string& file = std::string(),
                     uint line=0) throw();
     friend std::ostream& operator<<(std::ostream& os,
                                     const RangeException& rhs);
@@ -174,8 +177,8 @@ class ResourceException : public Exception
 {
 public:
     ResourceException() throw();
-    ResourceException(std::string description = std::string(),
-                        std::string file = std::string(),
+    ResourceException(const std::string& description = std::string(),
+                        const std::string& file = std::string(),
                         uint line=0) throw();
     friend std::ostream& operator<<(std::ostream& os,
                                     const ResourceException& rhs);
@@ -205,8 +208,8 @@ class Error : public Throwable
 {
 public:
     Error() throw();
-    Error(std::string description = std::string(),
-            std::string file = std::string(),
+    Error(const std::string&description = std::string(),
+            const std::string& file = std::string(),
             uint line=0) throw();
     friend std::ostream& operator<<(std::ostream& os,
                                     const Error& rhs);
@@ -224,8 +227,8 @@ class MemoryError : public Error
 {
 public:
     MemoryError() throw();
-    MemoryError(std::string description = std::string(),
-                std::string file = std::string(),
+    MemoryError(const std::string& description = std::string(),
+                const std::string& file = std::string(),
                 uint line=0) throw();
     friend std::ostream& operator<<(std::ostream& os,
                                     const MemoryError& rhs);
@@ -244,8 +247,8 @@ class APIError : public Error
 {
 public:
     APIError() throw();
-    APIError(std::string description = std::string(),
-                std::string file = std::string(),
+    APIError(const std::string& description = std::string(),
+                const std::string& file = std::string(),
                 uint line=0) throw();
     friend std::ostream& operator<<(std::ostream& os,
                                     const APIError& rhs);
diff --git a/include/types.h b/include/types.h
index 247b071..5bc2e18 100644
--- a/include/types.h
+++ b/include/types.h
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: types.h,v 1.2 2005/02/04 08:12:14 cozman Exp $
+//  $Id: types.h,v 1.3 2005/02/07 01:48:26 cozman Exp $
 //
 // Revisions:
 //  $Log: types.h,v $
+//  Revision 1.3  2005/02/07 01:48:26  cozman
+//  string references
+//
 //  Revision 1.2  2005/02/04 08:12:14  cozman
 //  shared_ptr
 //
@@ -22,6 +25,9 @@
 
 #include <boost/shared_ptr.hpp>
 
+#include <string>
+#include <vector>
+
 // Title: Basic Types
 
 namespace photon {
@@ -40,6 +46,10 @@ namespace photon {
     //  Scalar value, used throughout photon. (double or float)
     typedef double scalar;
     
+    // Type: StrVec
+    //  Typedef for vector of strings, which is used all throughout photon.
+    typedef std::vector<std::string> StrVec;
+    
     // Type: shared_ptr
     //  Shared pointer type. (uses the boost implementation)
     using boost::shared_ptr;
diff --git a/include/util/FileBuffer.h b/include/util/FileBuffer.h
index 5d433a8..59696eb 100644
--- a/include/util/FileBuffer.h
+++ b/include/util/FileBuffer.h
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: FileBuffer.h,v 1.1 2005/02/06 21:30:10 cozman Exp $
+//  $Id: FileBuffer.h,v 1.2 2005/02/07 01:48:26 cozman Exp $
 //
 // Revisions:
 //  $Log: FileBuffer.h,v $
+//  Revision 1.2  2005/02/07 01:48:26  cozman
+//  string references
+//
 //  Revision 1.1  2005/02/06 21:30:10  cozman
 //  PhysFS initial integration
 //
@@ -46,7 +49,7 @@ public:
     //
     // Parameters:
     //   filename - Name of file to load.
-    FileBuffer(std::string filename);
+    FileBuffer(const std::string& filename);
 
     //  Function: ~FileBuffer
     //  Destructor, calls <close>.
@@ -60,7 +63,7 @@ public:
     //
     // Parameters:
     //   filename - Name of file to load.
-    void open(std::string filename);
+    void open(const std::string& filename);
 
     // Function: close
     //  Frees memory occupied by loaded data.
@@ -95,7 +98,7 @@ public:
     //   Size of currently loaded data.
     uint getSize() const;
     
-    // Function: eof
+    // Function: isEOF
     //  Checks if internal cursor is at end of file.
     //
     // Returns:
diff --git a/include/util/VersionInfo.h b/include/util/VersionInfo.h
index 8d730e3..b25c670 100644
--- a/include/util/VersionInfo.h
+++ b/include/util/VersionInfo.h
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: VersionInfo.h,v 1.2 2005/02/05 02:57:07 cozman Exp $
+//  $Id: VersionInfo.h,v 1.3 2005/02/07 01:48:26 cozman Exp $
 //
 // Revisions:
 //  $Log: VersionInfo.h,v $
+//  Revision 1.3  2005/02/07 01:48:26  cozman
+//  string references
+//
 //  Revision 1.2  2005/02/05 02:57:07  cozman
 //  *** empty log message ***
 //
@@ -31,32 +34,32 @@ namespace util {
 //  Format is Major.Minor.Release [ExtraInfo].
 //
 // Operators:
-//   VersionInfo < VersionInfo
-//   VersionInfo <= VersionInfo
-//   VersionInfo == VersionInfo
-//   VersionInfo >= VersionInfo
-//   VersionInfo > VersionInfo
-//   ostream& << VersionInfo
+//   - VersionInfo < VersionInfo
+//   - VersionInfo <= VersionInfo
+//   - VersionInfo == VersionInfo
+//   - VersionInfo >= VersionInfo
+//   - VersionInfo > VersionInfo
+//   - ostream& << VersionInfo
 class VersionInfo
 {
 public:
     // Group: Variables
 
-    // Variable: Major
+    // Variable: major
     //  Major version number, should be changed when major changes take place.
     unsigned int major;
 
-    // Variable: Minor
+    // Variable: minor
     //  Minor version number, should be changed when key features are
     //  added/removed/changed.
     unsigned int minor;
 
-    // Variable: Release
+    // Variable: release
     //  Release number, should be changed upon every release that isn't
     //  signifigant enough to reflect a change in the minor versioning number.
     unsigned int release;
 
-    // Variable: Extra
+    // Variable: extra
     //  String for holding extra data, such as a release name or special tag.
     std::string extra;
 
diff --git a/src/Log.cpp b/src/Log.cpp
index 603f202..f4533be 100644
--- a/src/Log.cpp
+++ b/src/Log.cpp
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: Log.cpp,v 1.2 2005/02/04 08:11:54 cozman Exp $
+//  $Id: Log.cpp,v 1.3 2005/02/07 01:48:27 cozman Exp $
 //
 // Revisions:
 //  $Log: Log.cpp,v $
+//  Revision 1.3  2005/02/07 01:48:27  cozman
+//  string references
+//
 //  Revision 1.2  2005/02/04 08:11:54  cozman
 //  switched Log to shared_ptrs and added extra flushes
 //
@@ -53,7 +56,7 @@ void Log::addSink(LogSinkPtr sink)
     sinks_.push_back(sink);
 }
 
-void Log::removeSink(std::string sinkName)
+void Log::removeSink(const std::string& sinkName)
 {
     flush();
     
diff --git a/src/LogSink.cpp b/src/LogSink.cpp
index 84d3a4a..2dbb462 100644
--- a/src/LogSink.cpp
+++ b/src/LogSink.cpp
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: LogSink.cpp,v 1.4 2005/02/05 03:01:04 cozman Exp $
+//  $Id: LogSink.cpp,v 1.5 2005/02/07 01:48:27 cozman Exp $
 //
 // Revisions:
 //  $Log: LogSink.cpp,v $
+//  Revision 1.5  2005/02/07 01:48:27  cozman
+//  string references
+//
 //  Revision 1.4  2005/02/05 03:01:04  cozman
 //  removed getStream() (useless)
 //
@@ -32,7 +35,7 @@ namespace photon
 
 //LogSink
 
-LogSink::LogSink(std::string name) :
+LogSink::LogSink(const std::string& name) :
     name_(name)
 {
 }
@@ -48,7 +51,7 @@ std::string LogSink::getName() const
 
 //ConsoleSink
 
-ConsoleSink::ConsoleSink(std::string name) :
+ConsoleSink::ConsoleSink(const std::string& name) :
     LogSink(name)
 {
 }
@@ -57,7 +60,7 @@ ConsoleSink::~ConsoleSink()
 {
 }
 
-void ConsoleSink::writeMessage(LogLevel level, std::string msg)
+void ConsoleSink::writeMessage(LogLevel level, const std::string& msg)
 {
     static char* pre[] = { "    NOTE: ",
                            " VERBOSE: ",
@@ -70,7 +73,7 @@ void ConsoleSink::writeMessage(LogLevel level, std::string msg)
 
 //TextSink
 
-TextSink::TextSink(std::string name) :
+TextSink::TextSink(const std::string& name) :
     LogSink(name),
     out_(std::string(name+".txt").c_str())
 {
@@ -81,7 +84,7 @@ TextSink::~TextSink()
     out_.close();
 }
 
-void TextSink::writeMessage(LogLevel level, std::string msg)
+void TextSink::writeMessage(LogLevel level, const std::string& msg)
 {
     static char* pre[] = { "    NOTE: ",
                            " VERBOSE: ",
@@ -94,7 +97,7 @@ void TextSink::writeMessage(LogLevel level, std::string msg)
 
 //HTMLSink
 
-HTMLSink::HTMLSink(std::string name) :
+HTMLSink::HTMLSink(const std::string& name) :
     LogSink(name),
     out_(std::string(name+".html").c_str())
 {
@@ -118,7 +121,7 @@ HTMLSink::~HTMLSink()
     out_.close();
 }
 
-void HTMLSink::writeMessage(LogLevel level, std::string msg)
+void HTMLSink::writeMessage(LogLevel level, const std::string& msg)
 {
     static char* css[] = {"note","verbose","warning","error","critical"};
     static char* pre[] = { "    NOTE: ",
diff --git a/src/exceptions.cpp b/src/exceptions.cpp
index 55488f4..ab47520 100644
--- a/src/exceptions.cpp
+++ b/src/exceptions.cpp
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: exceptions.cpp,v 1.2 2005/01/31 15:44:38 cozman Exp $
+//  $Id: exceptions.cpp,v 1.3 2005/02/07 01:48:27 cozman Exp $
 //
 // Revisions:
 //  $Log: exceptions.cpp,v $
+//  Revision 1.3  2005/02/07 01:48:27  cozman
+//  string references
+//
 //  Revision 1.2  2005/01/31 15:44:38  cozman
 //  simplified exceptions
 //
@@ -24,8 +27,8 @@
 namespace photon 
 {
 
-Throwable::Throwable(std::string description,
-                        std::string file, uint line) throw() :
+Throwable::Throwable(const std::string& description,
+                        const std::string& file, uint line) throw() :
     description_(description), file_(file), line_(line)
 {}
 
@@ -46,40 +49,40 @@ std::string Throwable::getDesc() const throw()
 
 //exceptions//
 
-Exception::Exception(std::string description,
-                        std::string file, uint line) throw() :
+Exception::Exception(const std::string& description,
+                        const std::string& file, uint line) throw() :
     Throwable(description,file,line) {}
 std::ostream& operator<<(std::ostream& os, const Exception& rhs)
 {
     return os << "General exception occured: " << rhs.getDesc();
 }
 
-ArgumentException::ArgumentException(std::string description,
-                                    std::string file, uint line) throw() :
+ArgumentException::ArgumentException(const std::string& description,
+                                const std::string& file, uint line) throw() :
     Exception(description,file,line) {}
 std::ostream& operator<<(std::ostream& os, const ArgumentException& rhs)
 {
     return os << "Invalid argument exception occured. " << rhs.getDesc();
 }
 
-PreconditionException::PreconditionException(std::string description,
-                                        std::string file, uint line) throw() :
+PreconditionException::PreconditionException(const std::string& description,
+                                const std::string& file, uint line) throw() :
     Exception(description,file,line) {}
 std::ostream& operator<<(std::ostream& os, const PreconditionException& rhs)
 {
     return os << "Precondition exception occured: " << rhs.getDesc();
 }
 
-RangeException::RangeException(std::string description,
-                                std::string file, uint line) throw() :
+RangeException::RangeException(const std::string& description,
+                                const std::string& file, uint line) throw() :
     Exception(description,file,line) {}
 std::ostream& operator<<(std::ostream& os, const RangeException& rhs)
 {
     return os << "Out-of-range exception: " << rhs.getDesc();
 }
 
-ResourceException::ResourceException(std::string description,
-                                        std::string file, uint line) throw() :
+ResourceException::ResourceException(const std::string& description,
+                                const std::string& file, uint line) throw() :
     Exception(description,file,line) {}
 std::ostream& operator<<(std::ostream& os, const ResourceException& rhs)
 {
@@ -88,23 +91,24 @@ std::ostream& operator<<(std::ostream& os, const ResourceException& rhs)
 
 //errors//
 
-Error::Error(std::string description, std::string file, uint line) throw() :
+Error::Error(const std::string& description,
+                const std::string& file, uint line) throw() :
     Throwable(description,file,line) {}
 std::ostream& operator<<(std::ostream& os, const Error& rhs)
 {
     return os << "General error occured: " << rhs.getDesc();
 }
 
-MemoryError::MemoryError(std::string description,
-                            std::string file, uint line) throw() :
+MemoryError::MemoryError(const std::string& description,
+                            const std::string& file, uint line) throw() :
     Error(description,file,line) {}
 std::ostream& operator<<(std::ostream& os, const MemoryError& rhs)
 {
     return os << "Memory error occured: " << rhs.getDesc();
 }
 
-APIError::APIError(std::string description,
-                    std::string file, uint line) throw() :
+APIError::APIError(const std::string& description,
+                    const std::string& file, uint line) throw() :
     Error(description,file,line) {}
 std::ostream& operator<<(std::ostream& os, const APIError& rhs)
 {
diff --git a/src/util/FileBuffer.cpp b/src/util/FileBuffer.cpp
index 4aa0fd6..bc3af09 100644
--- a/src/util/FileBuffer.cpp
+++ b/src/util/FileBuffer.cpp
@@ -5,10 +5,13 @@
 //  James Turk (jpt2433@rit.edu)
 //
 // Version:
-//  $Id: FileBuffer.cpp,v 1.1 2005/02/06 21:30:10 cozman Exp $
+//  $Id: FileBuffer.cpp,v 1.2 2005/02/07 01:48:27 cozman Exp $
 //
 // Revisions:
 //  $Log: FileBuffer.cpp,v $
+//  Revision 1.2  2005/02/07 01:48:27  cozman
+//  string references
+//
 //  Revision 1.1  2005/02/06 21:30:10  cozman
 //  PhysFS initial integration
 //
@@ -28,14 +31,14 @@ FileBuffer::FileBuffer() :
 {}
 
 
-FileBuffer::FileBuffer(std::string filename) :
+FileBuffer::FileBuffer(const std::string& filename) :
     file_( PHYSFS_openRead(filename.c_str()) )
 {}
 
 FileBuffer::~FileBuffer()
 {}
 
-void FileBuffer::open(std::string filename)
+void FileBuffer::open(const std::string& filename)
 {
     file_ = PHYSFS_openRead(filename.c_str());
 }