diff --git a/OOP_1A2_Project/bin/.gitignore b/OOP_1A2_Project/bin/.gitignore
index 5c7ebe3..ac72981 100644
--- a/OOP_1A2_Project/bin/.gitignore
+++ b/OOP_1A2_Project/bin/.gitignore
@@ -1,2 +1,2 @@
-/backend/
 /windowInterface/
+/backend/
diff --git a/OOP_1A2_Project/bin/backend/Board.class b/OOP_1A2_Project/bin/backend/Board.class
index 92e7fab..8d5e10f 100644
Binary files a/OOP_1A2_Project/bin/backend/Board.class and b/OOP_1A2_Project/bin/backend/Board.class differ
diff --git a/OOP_1A2_Project/src/backend/Board.java b/OOP_1A2_Project/src/backend/Board.java
index 74c2f9d..8462fd9 100644
--- a/OOP_1A2_Project/src/backend/Board.java
+++ b/OOP_1A2_Project/src/backend/Board.java
@@ -2,6 +2,7 @@ package backend;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Stack;
 
 public class Board {
     private int width;
@@ -10,11 +11,13 @@ public class Board {
     private boolean isWhiteTurn;
     private ArrayList<Piece> pieces;
     private List<Move.Position> highlightedPositions = new ArrayList<>();
+    
+    // Add this for undo functionality
+    private Stack<Board> boardHistory = new Stack<>();
 
     private Integer selectedX = null;
     private Integer selectedY = null;
-
-  
+    
     public Board(int colNum, int lineNum) {
         this.width = colNum;
         this.height = lineNum;
@@ -22,37 +25,30 @@ public class Board {
         this.isWhiteTurn = true;
         this.pieces = new ArrayList<>();
         this.highlightedPositions = new ArrayList<>();
+        this.boardHistory = new Stack<>();
     }
 
-    
     public int getWidth() {
         return width;
     }
 
-    
     public int getHeight() {
         return height;
     }
 
-
     public int getTurnNumber() {
         return turnNumber;
     }
 
-
-
     public boolean isTurnWhite() {
         return isWhiteTurn;
     }
-    
-
 
     public void advanceTurn() {
         turnNumber++;
         isWhiteTurn = !isWhiteTurn;
     }
 
-
     public void setPiece(boolean isWhite, PieceType type, int x, int y) {
         for (int i = 0; i < pieces.size(); i++) {
             Piece p = pieces.get(i);
@@ -65,7 +61,6 @@ public class Board {
         pieces.add(newPiece);
     }
     
-    
     public void removePiece(int x, int y) {
         for (int i = 0; i < pieces.size(); i++) {
             Piece p = pieces.get(i);
@@ -76,7 +71,6 @@ public class Board {
         }
     }
 
-
     public void populateBoard() {
         cleanBoard();
         
@@ -113,12 +107,10 @@ public class Board {
         pieces.add(new Piece(6, 7, knight, true));
         pieces.add(new Piece(7, 7, rook, true));
     }
-    
 
     public void cleanBoard() {
         pieces.clear();
     }
-    
 
     public String toString() {
         String result = "";
@@ -141,7 +133,6 @@ public class Board {
         }
         return result;
     }
-    
 
     public ArrayList<Piece> getPieces() {
         ArrayList<Piece> result = new ArrayList<>();
@@ -150,7 +141,6 @@ public class Board {
         }
         return result;
     }
-    
 
     public Piece getPieceAt(int x, int y) {
         for (Piece p : pieces) {
@@ -161,7 +151,6 @@ public class Board {
         return null;
     }
 
-
     public void userTouch(int x, int y) {
         Piece clickedPiece = getPieceAt(x, y);
 
@@ -180,6 +169,9 @@ public class Board {
                 Piece selectedPiece = getPieceAt(selectedX, selectedY);
                 if (selectedPiece != null) {
                     if (isHighlighted(x, y)) {
+                        // SAVE STATE BEFORE MOVE
+                        saveCurrentState();
+                        
                         Move move = new Move(selectedX, selectedY, x, y, this);
                         if (move.isValid()) {
                             move.execute();
@@ -217,7 +209,6 @@ public class Board {
         }
         return false; 
     }
-    
 
     public String[] toFileRep() {
         String[] fileRep = new String[height + 1];
@@ -239,11 +230,11 @@ public class Board {
         return fileRep;
     }
 
-
     public Board(String[] array) {
         this.width = 8;
         this.height = 8;
         this.pieces = new ArrayList<>();
+        this.boardHistory = new Stack<>();
         
         for (int y = 0; y < height; y++) {
             if (y >= array.length) {
@@ -292,7 +283,6 @@ public class Board {
             this.isWhiteTurn = true;
         }
     }
-    
 
     public boolean isHighlighted(int x, int y) {
         for (Move.Position pos : highlightedPositions) {
@@ -303,12 +293,6 @@ public class Board {
         return false;
     }
 
-
-    public void undoLastMove() {
-        // TODO
-    }
-
-
     public Board(Board board) {
         this.width = board.width;
         this.height = board.height;
@@ -328,14 +312,15 @@ public class Board {
         // Copy highlighted positions
         this.highlightedPositions = new ArrayList<>();
         this.highlightedPositions.addAll(board.highlightedPositions);
+        
+        // Initialize board history for copy constructor
+        this.boardHistory = new Stack<>();
     }
-    
  
     private void clearHighlights() {
         highlightedPositions.clear();
     }
 
-
     private void calculateHighlights() {
         if (selectedX == null || selectedY == null) {
             return;
@@ -354,14 +339,41 @@ public class Board {
         highlightedPositions.clear();
         highlightedPositions.addAll(validMoves);
     }
-    
 
     public void playMove(Move move) {
         if (move.isValid() && !move.putsOwnKingInCheck()) {
+            // SAVE STATE BEFORE MOVE
+            saveCurrentState();
+            
             move.execute();
             
-         // Play the move sound
+            // Play the move sound
             Sound.getInstance().playMoveSound();
         }
     }
+
+    private void saveCurrentState() {
+        boardHistory.push(new Board(this));
+    }
+
+    public void undoLastMove() {
+        if (!boardHistory.isEmpty()) {
+            Board previousBoard = boardHistory.pop();
+            this.width = previousBoard.width;
+            this.height = previousBoard.height;
+            this.turnNumber = previousBoard.turnNumber;
+            this.isWhiteTurn = previousBoard.isWhiteTurn;
+            this.pieces.clear();
+            for (Piece p : previousBoard.getPieces()) {
+                this.pieces.add(new Piece(p.getX(), p.getY(), p.getType(), p.isWhite()));
+            }
+            selectedX = null;
+            selectedY = null;
+            clearHighlights();
+        }
+    }
+    
+    public boolean canUndo() {
+        return !boardHistory.isEmpty();
+    }
 }
\ No newline at end of file