diff --git a/02/ALU-basic.cmp b/02/ALU-basic.cmp
new file mode 100644
index 0000000..249461c
--- /dev/null
+++ b/02/ALU-basic.cmp
@@ -0,0 +1,37 @@
+|        x         |        y         |zx |nx |zy |ny | f |no |       out        |
+| 0000000000000000 | 1111111111111111 | 1 | 0 | 1 | 0 | 1 | 0 | 0000000000000000 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 1 | 1 | 1 | 1 | 0000000000000001 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 1 | 0 | 1 | 0 | 1111111111111111 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 1 | 1 | 0 | 0 | 0000000000000000 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 0 | 0 | 0 | 1111111111111111 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 1 | 1 | 0 | 1 | 1111111111111111 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 0 | 0 | 1 | 0000000000000000 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 1 | 1 | 1 | 1 | 0000000000000000 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 0 | 1 | 1 | 0000000000000001 |
+| 0000000000000000 | 1111111111111111 | 0 | 1 | 1 | 1 | 1 | 1 | 0000000000000001 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 1 | 1 | 1 | 0000000000000000 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 1 | 1 | 1 | 0 | 1111111111111111 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 0 | 1 | 0 | 1111111111111110 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 0 | 0 | 1 | 0 | 1111111111111111 |
+| 0000000000000000 | 1111111111111111 | 0 | 1 | 0 | 0 | 1 | 1 | 0000000000000001 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 0 | 1 | 1 | 1 | 1111111111111111 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 0 | 0 | 0 | 0 | 0000000000000000 |
+| 0000000000000000 | 1111111111111111 | 0 | 1 | 0 | 1 | 0 | 1 | 1111111111111111 |
+| 0101101110100000 | 0001111011010010 | 1 | 0 | 1 | 0 | 1 | 0 | 0000000000000000 |
+| 0101101110100000 | 0001111011010010 | 1 | 1 | 1 | 1 | 1 | 1 | 0000000000000001 |
+| 0101101110100000 | 0001111011010010 | 1 | 1 | 1 | 0 | 1 | 0 | 1111111111111111 |
+| 0101101110100000 | 0001111011010010 | 0 | 0 | 1 | 1 | 0 | 0 | 0101101110100000 |
+| 0101101110100000 | 0001111011010010 | 1 | 1 | 0 | 0 | 0 | 0 | 0001111011010010 |
+| 0101101110100000 | 0001111011010010 | 0 | 0 | 1 | 1 | 0 | 1 | 1010010001011111 |
+| 0101101110100000 | 0001111011010010 | 1 | 1 | 0 | 0 | 0 | 1 | 1110000100101101 |
+| 0101101110100000 | 0001111011010010 | 0 | 0 | 1 | 1 | 1 | 1 | 1010010001100000 |
+| 0101101110100000 | 0001111011010010 | 1 | 1 | 0 | 0 | 1 | 1 | 1110000100101110 |
+| 0101101110100000 | 0001111011010010 | 0 | 1 | 1 | 1 | 1 | 1 | 0101101110100001 |
+| 0101101110100000 | 0001111011010010 | 1 | 1 | 0 | 1 | 1 | 1 | 0001111011010011 |
+| 0101101110100000 | 0001111011010010 | 0 | 0 | 1 | 1 | 1 | 0 | 0101101110011111 |
+| 0101101110100000 | 0001111011010010 | 1 | 1 | 0 | 0 | 1 | 0 | 0001111011010001 |
+| 0101101110100000 | 0001111011010010 | 0 | 0 | 0 | 0 | 1 | 0 | 0111101001110010 |
+| 0101101110100000 | 0001111011010010 | 0 | 1 | 0 | 0 | 1 | 1 | 0011110011001110 |
+| 0101101110100000 | 0001111011010010 | 0 | 0 | 0 | 1 | 1 | 1 | 1100001100110010 |
+| 0101101110100000 | 0001111011010010 | 0 | 0 | 0 | 0 | 0 | 0 | 0001101010000000 |
+| 0101101110100000 | 0001111011010010 | 0 | 1 | 0 | 1 | 0 | 1 | 0101111111110010 |
diff --git a/02/ALU-basic.tst b/02/ALU-basic.tst
new file mode 100644
index 0000000..b26335e
--- /dev/null
+++ b/02/ALU-basic.tst
@@ -0,0 +1,344 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/ALU-basic.tst
+
+// Tests the basic version of the ALU chip.
+// DOES NOT replace the final test provided by ALU.tst.
+// Specifically: Tests the ALU logic that computes the 'out' output;
+// The 'zr' and 'ng' output bits are ignored.
+
+load ALU.hdl,
+output-file ALU-basic.out,
+compare-to ALU-basic.cmp,
+output-list x%B1.16.1 y%B1.16.1 zx nx zy ny f no out%B1.16.1;
+
+set x %B0000000000000000,
+set y %B1111111111111111,
+
+set zx 1,
+set nx 0,
+set zy 1,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 1,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  0,
+set no 0,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  0,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  0,
+set no 1,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  0,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 1,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 0,
+set f  0,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 1,
+set zy 0,
+set ny 1,
+set f  0,
+set no 1,
+eval,
+output;
+
+set x %B101101110100000,
+set y %B001111011010010,
+
+set zx 1,
+set nx 0,
+set zy 1,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 1,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  0,
+set no 0,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  0,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  0,
+set no 1,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  0,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 1,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 0,
+set f  0,
+set no 0,
+eval,
+output;
+
+set zx 0,
+set nx 1,
+set zy 0,
+set ny 1,
+set f  0,
+set no 1,
+eval,
+output;
diff --git a/02/ALU.cmp b/02/ALU.cmp
new file mode 100644
index 0000000..2424a73
--- /dev/null
+++ b/02/ALU.cmp
@@ -0,0 +1,37 @@
+|        x         |        y         |zx |nx |zy |ny | f |no |       out        |zr |ng |
+| 0000000000000000 | 1111111111111111 | 1 | 0 | 1 | 0 | 1 | 0 | 0000000000000000 | 1 | 0 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 1 | 1 | 1 | 1 | 0000000000000001 | 0 | 0 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 1 | 0 | 1 | 0 | 1111111111111111 | 0 | 1 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 1 | 1 | 0 | 0 | 0000000000000000 | 1 | 0 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 0 | 0 | 0 | 1111111111111111 | 0 | 1 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 1 | 1 | 0 | 1 | 1111111111111111 | 0 | 1 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 0 | 0 | 1 | 0000000000000000 | 1 | 0 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 1 | 1 | 1 | 1 | 0000000000000000 | 1 | 0 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 0 | 1 | 1 | 0000000000000001 | 0 | 0 |
+| 0000000000000000 | 1111111111111111 | 0 | 1 | 1 | 1 | 1 | 1 | 0000000000000001 | 0 | 0 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 1 | 1 | 1 | 0000000000000000 | 1 | 0 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 1 | 1 | 1 | 0 | 1111111111111111 | 0 | 1 |
+| 0000000000000000 | 1111111111111111 | 1 | 1 | 0 | 0 | 1 | 0 | 1111111111111110 | 0 | 1 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 0 | 0 | 1 | 0 | 1111111111111111 | 0 | 1 |
+| 0000000000000000 | 1111111111111111 | 0 | 1 | 0 | 0 | 1 | 1 | 0000000000000001 | 0 | 0 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 0 | 1 | 1 | 1 | 1111111111111111 | 0 | 1 |
+| 0000000000000000 | 1111111111111111 | 0 | 0 | 0 | 0 | 0 | 0 | 0000000000000000 | 1 | 0 |
+| 0000000000000000 | 1111111111111111 | 0 | 1 | 0 | 1 | 0 | 1 | 1111111111111111 | 0 | 1 |
+| 0000000000010001 | 0000000000000011 | 1 | 0 | 1 | 0 | 1 | 0 | 0000000000000000 | 1 | 0 |
+| 0000000000010001 | 0000000000000011 | 1 | 1 | 1 | 1 | 1 | 1 | 0000000000000001 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 1 | 1 | 1 | 0 | 1 | 0 | 1111111111111111 | 0 | 1 |
+| 0000000000010001 | 0000000000000011 | 0 | 0 | 1 | 1 | 0 | 0 | 0000000000010001 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 1 | 1 | 0 | 0 | 0 | 0 | 0000000000000011 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 0 | 0 | 1 | 1 | 0 | 1 | 1111111111101110 | 0 | 1 |
+| 0000000000010001 | 0000000000000011 | 1 | 1 | 0 | 0 | 0 | 1 | 1111111111111100 | 0 | 1 |
+| 0000000000010001 | 0000000000000011 | 0 | 0 | 1 | 1 | 1 | 1 | 1111111111101111 | 0 | 1 |
+| 0000000000010001 | 0000000000000011 | 1 | 1 | 0 | 0 | 1 | 1 | 1111111111111101 | 0 | 1 |
+| 0000000000010001 | 0000000000000011 | 0 | 1 | 1 | 1 | 1 | 1 | 0000000000010010 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 1 | 1 | 0 | 1 | 1 | 1 | 0000000000000100 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 0 | 0 | 1 | 1 | 1 | 0 | 0000000000010000 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 1 | 1 | 0 | 0 | 1 | 0 | 0000000000000010 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 0 | 0 | 0 | 0 | 1 | 0 | 0000000000010100 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 0 | 1 | 0 | 0 | 1 | 1 | 0000000000001110 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 0 | 0 | 0 | 1 | 1 | 1 | 1111111111110010 | 0 | 1 |
+| 0000000000010001 | 0000000000000011 | 0 | 0 | 0 | 0 | 0 | 0 | 0000000000000001 | 0 | 0 |
+| 0000000000010001 | 0000000000000011 | 0 | 1 | 0 | 1 | 0 | 1 | 0000000000010011 | 0 | 0 |
diff --git a/02/ALU.hdl b/02/ALU.hdl
new file mode 100644
index 0000000..0258077
--- /dev/null
+++ b/02/ALU.hdl
@@ -0,0 +1,45 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/ALU.hdl
+/**
+ * ALU (Arithmetic Logic Unit):
+ * Computes out = one of the following functions:
+ *                0, 1, -1,
+ *                x, y, !x, !y, -x, -y,
+ *                x + 1, y + 1, x - 1, y - 1,
+ *                x + y, x - y, y - x,
+ *                x & y, x | y
+ * on the 16-bit inputs x, y,
+ * according to the input bits zx, nx, zy, ny, f, no.
+ * In addition, computes the two output bits:
+ * if (out == 0) zr = 1, else zr = 0
+ * if (out < 0)  ng = 1, else ng = 0
+ */
+// Implementation: Manipulates the x and y inputs
+// and operates on the resulting values, as follows:
+// if (zx == 1) sets x = 0        // 16-bit constant
+// if (nx == 1) sets x = !x       // bitwise not
+// if (zy == 1) sets y = 0        // 16-bit constant
+// if (ny == 1) sets y = !y       // bitwise not
+// if (f == 1)  sets out = x + y  // integer 2's complement addition
+// if (f == 0)  sets out = x & y  // bitwise and
+// if (no == 1) sets out = !out   // bitwise not
+
+CHIP ALU {
+    IN  
+        x[16], y[16],  // 16-bit inputs        
+        zx, // zero the x input?
+        nx, // negate the x input?
+        zy, // zero the y input?
+        ny, // negate the y input?
+        f,  // compute (out = x + y) or (out = x & y)?
+        no; // negate the out output?
+    OUT 
+        out[16], // 16-bit output
+        zr,      // if (out == 0) equals 1, else 0
+        ng;      // if (out < 0)  equals 1, else 0
+
+    PARTS:
+    //// Replace this comment with your code.
+}
\ No newline at end of file
diff --git a/02/ALU.tst b/02/ALU.tst
new file mode 100644
index 0000000..9d79990
--- /dev/null
+++ b/02/ALU.tst
@@ -0,0 +1,375 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/ALU.tst
+
+load ALU.hdl,
+output-file ALU.out,
+compare-to ALU.cmp,
+output-list x%B1.16.1 y%B1.16.1 zx nx zy ny f no out%B1.16.1 zr ng;
+
+set x %B0000000000000000,  // x = 0
+set y %B1111111111111111;  // y = -1
+
+// Compute 0
+set zx 1,
+set nx 0,
+set zy 1,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute 1
+set zx 1,
+set nx 1,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute -1
+set zx 1,
+set nx 1,
+set zy 1,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute x
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  0,
+set no 0,
+eval,
+output;
+
+// Compute y
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  0,
+set no 0,
+eval,
+output;
+
+// Compute !x
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  0,
+set no 1,
+eval,
+output;
+
+// Compute !y
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  0,
+set no 1,
+eval,
+output;
+
+// Compute -x
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute -y
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute x + 1
+set zx 0,
+set nx 1,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute y + 1
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute x - 1
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute y - 1
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute x + y
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute x - y
+set zx 0,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute y - x
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute x & y
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 0,
+set f  0,
+set no 0,
+eval,
+output;
+
+// Compute x | y
+set zx 0,
+set nx 1,
+set zy 0,
+set ny 1,
+set f  0,
+set no 1,
+eval,
+output;
+
+set x %B000000000010001,  // x = 17
+set y %B000000000000011;  // y =  3
+
+// Compute 0
+set zx 1,
+set nx 0,
+set zy 1,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute 1
+set zx 1,
+set nx 1,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute -1
+set zx 1,
+set nx 1,
+set zy 1,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute x
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  0,
+set no 0,
+eval,
+output;
+
+// Compute y
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  0,
+set no 0,
+eval,
+output;
+
+// Compute !x
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  0,
+set no 1,
+eval,
+output;
+
+// Compute !y
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  0,
+set no 1,
+eval,
+output;
+
+// Compute -x
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute -y
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute x + 1
+set zx 0,
+set nx 1,
+set zy 1,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute y + 1
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute x - 1
+set zx 0,
+set nx 0,
+set zy 1,
+set ny 1,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute y - 1
+set zx 1,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute x + y
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 0,
+set f  1,
+set no 0,
+eval,
+output;
+
+// Compute x - y
+set zx 0,
+set nx 1,
+set zy 0,
+set ny 0,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute y - x
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 1,
+set f  1,
+set no 1,
+eval,
+output;
+
+// Compute x & y
+set zx 0,
+set nx 0,
+set zy 0,
+set ny 0,
+set f  0,
+set no 0,
+eval,
+output;
+
+// Compute x | y
+set zx 0,
+set nx 1,
+set zy 0,
+set ny 1,
+set f  0,
+set no 1,
+eval,
+output;
diff --git a/02/Add16.cmp b/02/Add16.cmp
new file mode 100644
index 0000000..20f9c65
--- /dev/null
+++ b/02/Add16.cmp
@@ -0,0 +1,7 @@
+|        a         |        b         |       out        |
+| 0000000000000000 | 0000000000000000 | 0000000000000000 |
+| 0000000000000000 | 1111111111111111 | 1111111111111111 |
+| 1111111111111111 | 1111111111111111 | 1111111111111110 |
+| 1010101010101010 | 0101010101010101 | 1111111111111111 |
+| 0011110011000011 | 0000111111110000 | 0100110010110011 |
+| 0001001000110100 | 1001100001110110 | 1010101010101010 |
diff --git a/02/Add16.hdl b/02/Add16.hdl
new file mode 100644
index 0000000..f7609bf
--- /dev/null
+++ b/02/Add16.hdl
@@ -0,0 +1,15 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/Add16.hdl
+/**
+ * 16-bit adder: Adds two 16-bit two's complement values.
+ * The most significant carry bit is ignored.
+ */
+CHIP Add16 {
+    IN a[16], b[16];
+    OUT out[16];
+
+    PARTS:
+    //// Replace this comment with your code.
+}
\ No newline at end of file
diff --git a/02/Add16.tst b/02/Add16.tst
new file mode 100644
index 0000000..c2641d0
--- /dev/null
+++ b/02/Add16.tst
@@ -0,0 +1,39 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/Add16.tst
+
+load Add16.hdl,
+output-file Add16.out,
+compare-to Add16.cmp,
+output-list a%B1.16.1 b%B1.16.1 out%B1.16.1;
+
+set a %B0000000000000000,
+set b %B0000000000000000,
+eval,
+output;
+
+set a %B0000000000000000,
+set b %B1111111111111111,
+eval,
+output;
+
+set a %B1111111111111111,
+set b %B1111111111111111,
+eval,
+output;
+
+set a %B1010101010101010,
+set b %B0101010101010101,
+eval,
+output;
+
+set a %B0011110011000011,
+set b %B0000111111110000,
+eval,
+output;
+
+set a %B0001001000110100,
+set b %B1001100001110110,
+eval,
+output;
diff --git a/02/FullAdder.cmp b/02/FullAdder.cmp
new file mode 100644
index 0000000..90fbc1d
--- /dev/null
+++ b/02/FullAdder.cmp
@@ -0,0 +1,9 @@
+| a | b | c |sum|carry|
+| 0 | 0 | 0 | 0 |  0  |
+| 0 | 0 | 1 | 1 |  0  |
+| 0 | 1 | 0 | 1 |  0  |
+| 0 | 1 | 1 | 0 |  1  |
+| 1 | 0 | 0 | 1 |  0  |
+| 1 | 0 | 1 | 0 |  1  |
+| 1 | 1 | 0 | 0 |  1  |
+| 1 | 1 | 1 | 1 |  1  |
diff --git a/02/FullAdder.hdl b/02/FullAdder.hdl
new file mode 100644
index 0000000..8c987be
--- /dev/null
+++ b/02/FullAdder.hdl
@@ -0,0 +1,15 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/FullAdder.hdl
+/**
+ * Computes the sum of three bits.
+ */
+CHIP FullAdder {
+    IN a, b, c;  // 1-bit inputs
+    OUT sum,     // Right bit of a + b + c
+        carry;   // Left bit of a + b + c
+
+    PARTS:
+    //// Replace this comment with your code.
+}
\ No newline at end of file
diff --git a/02/FullAdder.tst b/02/FullAdder.tst
new file mode 100644
index 0000000..c793645
--- /dev/null
+++ b/02/FullAdder.tst
@@ -0,0 +1,47 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/FullAdder.tst
+
+load FullAdder.hdl,
+output-file FullAdder.out,
+compare-to FullAdder.cmp,
+output-list a b c sum carry%B2.1.2;
+
+set a 0,
+set b 0,
+set c 0,
+eval,
+output;
+
+set c 1,
+eval,
+output;
+
+set b 1,
+set c 0,
+eval,
+output;
+
+set c 1,
+eval,
+output;
+
+set a 1,
+set b 0,
+set c 0,
+eval,
+output;
+
+set c 1,
+eval,
+output;
+
+set b 1,
+set c 0,
+eval,
+output;
+
+set c 1,
+eval,
+output;
diff --git a/02/HalfAdder.cmp b/02/HalfAdder.cmp
new file mode 100644
index 0000000..d081087
--- /dev/null
+++ b/02/HalfAdder.cmp
@@ -0,0 +1,5 @@
+| a | b |sum|car|
+| 0 | 0 | 0 | 0 |
+| 0 | 1 | 1 | 0 |
+| 1 | 0 | 1 | 0 |
+| 1 | 1 | 0 | 1 |
diff --git a/02/HalfAdder.hdl b/02/HalfAdder.hdl
new file mode 100644
index 0000000..4f5900a
--- /dev/null
+++ b/02/HalfAdder.hdl
@@ -0,0 +1,15 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/HalfAdder.hdl
+/**
+ * Computes the sum of two bits.
+ */
+CHIP HalfAdder {
+    IN a, b;    // 1-bit inputs
+    OUT sum,    // Right bit of a + b 
+        carry;  // Left bit of a + b
+
+    PARTS:
+    //// Replace this comment with your code.
+}
diff --git a/02/HalfAdder.tst b/02/HalfAdder.tst
new file mode 100644
index 0000000..a73b092
--- /dev/null
+++ b/02/HalfAdder.tst
@@ -0,0 +1,29 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/HalfAdder.tst
+
+load HalfAdder.hdl,
+output-file HalfAdder.out,
+compare-to HalfAdder.cmp,
+output-list a b sum carry;
+
+set a 0,
+set b 0,
+eval,
+output;
+
+set a 0,
+set b 1,
+eval,
+output;
+
+set a 1,
+set b 0,
+eval,
+output;
+
+set a 1,
+set b 1,
+eval,
+output;
diff --git a/02/Inc16.cmp b/02/Inc16.cmp
new file mode 100644
index 0000000..78de1fe
--- /dev/null
+++ b/02/Inc16.cmp
@@ -0,0 +1,5 @@
+|        in        |       out        |
+| 0000000000000000 | 0000000000000001 |
+| 1111111111111111 | 0000000000000000 |
+| 0000000000000101 | 0000000000000110 |
+| 1111111111111011 | 1111111111111100 |
diff --git a/02/Inc16.hdl b/02/Inc16.hdl
new file mode 100644
index 0000000..00a1310
--- /dev/null
+++ b/02/Inc16.hdl
@@ -0,0 +1,15 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/Inc16.hdl
+/**
+ * 16-bit incrementer:
+ * out = in + 1
+ */
+CHIP Inc16 {
+    IN in[16];
+    OUT out[16];
+
+    PARTS:
+    //// Replace this comment with your code.
+}
\ No newline at end of file
diff --git a/02/Inc16.tst b/02/Inc16.tst
new file mode 100644
index 0000000..8a7a723
--- /dev/null
+++ b/02/Inc16.tst
@@ -0,0 +1,25 @@
+// This file is part of www.nand2tetris.org
+// and the book "The Elements of Computing Systems"
+// by Nisan and Schocken, MIT Press.
+// File name: projects/2/Inc16.tst
+
+load Inc16.hdl,
+output-file Inc16.out,
+compare-to Inc16.cmp,
+output-list in%B1.16.1 out%B1.16.1;
+
+set in %B0000000000000000,  // in = 0
+eval,
+output;
+
+set in %B1111111111111111,  // in = -1
+eval,
+output;
+
+set in %B0000000000000101,  // in = 5
+eval,
+output;
+
+set in %B1111111111111011,  // in = -5
+eval,
+output;