diff --git a/cs621/proj4/KnightsTour.java b/cs621/proj4/KnightsTour.java
index 74bca40..6e61895 100644
--- a/cs621/proj4/KnightsTour.java
+++ b/cs621/proj4/KnightsTour.java
@@ -5,6 +5,9 @@ import javax.swing.*;
 import javax.swing.event.*;
 import javax.swing.border.*;
 
+/**
+ * This class implements a GUI interface to the KnightsTourBoard class
+ */
 public class KnightsTour extends JFrame
 {
     private KnightsTourBoard m_ktBoard = new KnightsTourBoard(5, 5);
@@ -24,6 +27,9 @@ public class KnightsTour extends JFrame
     private JPanel m_boardPanel;
     private JLabel m_statusLabel;
 
+    /**
+     * Construct the KnightsTour GUI interface
+     */
     public KnightsTour()
     {
         super("Josh's Knight's Tour project for CS621");
@@ -103,6 +109,8 @@ public class KnightsTour extends JFrame
         setVisible(true);
     }
 
+    /* Create a JPanel containing a grid showing the step number
+     * for each board position in the KnightsTourBoard object */
     private void createBoardPanel()
     {
         int width = m_ktBoard.getWidth();
@@ -128,6 +136,7 @@ public class KnightsTour extends JFrame
         m_mainPanel.validate();
     }
 
+    /* This helper class catches actions that occur on JButton objects */
     private class ActionEventHandler implements ActionListener
     {
         private KnightsTour m_kt;
@@ -163,6 +172,10 @@ public class KnightsTour extends JFrame
         }
     }
 
+    /**
+     * Helper method to set up the Knight's Tour GUI board
+     * @param runit whether to run the tour or not (false means just reset board)
+     */
     private void setUpTour(boolean runit)
     {
         /* first validate input text fields */
@@ -207,16 +220,22 @@ public class KnightsTour extends JFrame
         }
     }
 
+    /* This class runs as a separate thread to actually call
+     * tour() on the KnightsTourBoard object. This way, the GUI
+     * stays responsive and the user can cancel the tour by clicking
+     * a button if it runs for too long. */
     private class TourThread implements Runnable
     {
         int m_startx, m_starty;
 
+        /* create the tour thread with the given starting position */
         public TourThread(int startx, int starty)
         {
             m_startx = startx;
             m_starty = starty;
         }
 
+        /* called when the thread starts executing */
         public void run()
         {
             if (m_ktBoard.tour(m_startx, m_starty))
@@ -249,6 +268,10 @@ public class KnightsTour extends JFrame
         }
     }
 
+    /**
+     * This method is invoked first when the program is run.
+     * It simply creates a KnightsTour GUI object
+     */
     public static void main(String[] args)
     {
         KnightsTour kt = new KnightsTour();
diff --git a/cs621/proj4/KnightsTourBoard.java b/cs621/proj4/KnightsTourBoard.java
index cfa6f43..fa0b795 100644
--- a/cs621/proj4/KnightsTourBoard.java
+++ b/cs621/proj4/KnightsTourBoard.java
@@ -1,10 +1,18 @@
 
+/**
+ * This class implements the model for the Knight's Tour problem.
+ */
 public class KnightsTourBoard
 {
     protected int m_width;
     protected int m_height;
     protected int[][] m_board;
 
+    /**
+     * Construct a Knight's Tour Board object
+     * @param width the width of the board
+     * @param height the height of the board
+     */
     KnightsTourBoard(int width, int height)
     {
         m_width = width;
@@ -12,10 +20,29 @@ public class KnightsTourBoard
         m_board = new int[width][height];
     }
 
+    /**
+     * @return the width of the board
+     */
     public int getWidth() { return m_width; }
+
+    /**
+     * @return the height of the board
+     */
     public int getHeight() { return m_height; }
+
+    /**
+     * @param x the x coordinate of the position in question
+     * @param y the y coordinate of the position in question
+     * @return the step number at the given position in the board
+     */
     public int getStepAt(int x, int y) { return m_board[x][y]; }
 
+    /**
+     * Attempt to run a Knight's Tour from the starting position
+     * @param startx the x coordinate of the starting position
+     * @param starty the y coordinate of the starting position
+     * @return true if it was possible to perform the tour, otherwise false
+     */
     public boolean tour(int startx, int starty)
     {
         for (int x = 0; x < m_width; x++)
@@ -25,6 +52,8 @@ public class KnightsTourBoard
         return tourFrom(2, startx, starty);
     }
 
+    /* recursive helper function to tour()
+     * which stores the current step number */
     private boolean tourFrom(int nextStep, int startx, int starty)
     {
 //        System.out.println("tourFrom(" + nextStep + ", " +
diff --git a/cs621/proj4/KnightsTourBoardTest.java b/cs621/proj4/KnightsTourBoardTest.java
index 45f4fb3..468c10b 100644
--- a/cs621/proj4/KnightsTourBoardTest.java
+++ b/cs621/proj4/KnightsTourBoardTest.java
@@ -1,6 +1,9 @@
 
 import junit.framework.TestCase;
 
+/**
+ * This class tests the KnightsTourBoard class with junit test cases.
+ */
 public class KnightsTourBoardTest extends TestCase
 {
     public void testKnightsTourBoardImpossible1()