diff --git a/Cargo.lock b/Cargo.lock
index 03604ef..43bd876 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3,6 +3,7 @@ name = "mahdi_os"
 version = "0.1.0"
 dependencies = [
  "rlibc 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "spin 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -10,3 +11,8 @@ name = "rlibc"
 version = "0.1.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
+[[package]]
+name = "spin"
+version = "0.3.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
diff --git a/Cargo.toml b/Cargo.toml
index d9156bd..7e32671 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -8,6 +8,7 @@ crate-type = ["staticlib"]
 
 [dependencies]
 rlibc = "0.1.4"
+spin = "0.3.4"
 
 [profile.dev]
 panic = "abort"
diff --git a/Makefile b/Makefile
index c8d14ad..ad251ad 100644
--- a/Makefile
+++ b/Makefile
@@ -29,7 +29,8 @@ $(iso): $(kernel) $(grub_cfg)
 					@rm -r build/isofiles
 
 $(kernel): cargo $(rust_os) $(assembly_object_files) $(linker_script)
-						@ld -n --gc-sections -T $(linker_script) -o $(kernel) $(assembly_object_files) $(rust_os)
+						@ld -n --gc-sections -T $(linker_script) -o $(kernel) \
+																		$(assembly_object_files) $(rust_os)
 
 cargo:
 	@cargo build --target $(target)
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..0d77d7c
--- /dev/null
+++ b/README.md
@@ -0,0 +1,4 @@
+mahdi-os
+========
+
+I followed [this tutorial](http://www.randomhacks.net/bare-metal-rust/) to write this, and then tweaked it further and customized it.
diff --git a/src/arch/x86_64/boot.asm b/src/arch/x86_64/boot.asm
index 2850beb..bea86b9 100644
--- a/src/arch/x86_64/boot.asm
+++ b/src/arch/x86_64/boot.asm
@@ -13,6 +13,7 @@ start:
 
 	call set_up_page_tables
 	call enable_paging
+
 	call set_up_SSE
 
 	lgdt [gdt64.pointer]
@@ -118,7 +119,7 @@ set_up_page_tables:
 	cmp ecx, 512			 ; if counter == 512, the whole P2 table is mapped
 	jne .map_p2_table
 
-ret
+	ret
 
 enable_paging:
 	; load P4 to cr3 register (cpu uses this to access the P4 table)
@@ -169,7 +170,7 @@ section .rodata
 gdt64:
 	dq 0 ; zero entry
 .code: equ $ - gdt64
-	dq (1 << 44) | (1 << 47) | (1 << 41) | (1 << 43) | (1 << 54) ; code segment
+	dq (1 << 44) | (1 << 47) | (1 << 41) | (1 << 43) | (1 << 53) ; code segment
 .data equ $ - gdt64
 	dq (1 << 44) | (1 << 47) | (1 << 41) ; data segment
 .pointer:
diff --git a/src/arch/x86_64/long_mode_init.asm b/src/arch/x86_64/long_mode_init.asm
index 6b23e1a..7678924 100644
--- a/src/arch/x86_64/long_mode_init.asm
+++ b/src/arch/x86_64/long_mode_init.asm
@@ -7,10 +7,10 @@ long_mode_start:
 	call rust_main
 
 	; rust main returned, print `OS returned!`
-	mov rax, 0x4f724f204f534f4f
-	mov [0xb8000], rax
-	mov rax, 0x4f724f754f744f65
-	mov [0xb8008], rax
-	mov rax, 0x4f214f644f654f6e
-	mov [0xb8010], rax
+	; mov rax, 0x4f724f204f534f4f
+	; mov [0xb8000], rax
+	; mov rax, 0x4f724f754f744f65
+	; mov [0xb8008], rax
+	; mov rax, 0x4f214f644f654f6e
+	; mov [0xb8010], rax
 	hlt
diff --git a/src/lib.rs b/src/lib.rs
index 19791bf..b108ffd 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,21 +1,22 @@
 #![feature(lang_items)]
 #![no_std]
+#![feature(unique)]
+#![feature(const_fn)]
 
 extern crate rlibc;
+extern crate spin;
+
+#[macro_use]
+mod vga_buffer;
+use vga_buffer::*;
 
 #[no_mangle]
 pub extern fn rust_main() {
 	// ATTENTION: we have a very small stack and no guard page
-	let hello = b"Hello World!";
-	let color_byte = 0x1f; // white foreground, blue background
-	
-	let mut hello_colored = [color_byte; 24];
-	for (i, char_byte) in hello.into_iter().enumerate() {
-		hello_colored[i*2] = *char_byte;
-	}
+	use core::fmt::Write;
 
-	let buffer_ptr = (0xb8000 + 1988) as *mut _;
-	unsafe { *buffer_ptr = hello_colored };
+	vga_buffer::clear_screen();
+	println!("Hello, this is Mahdi OS{}", "!");
 
 	loop {}
 }
diff --git a/src/vga_buffer.rs b/src/vga_buffer.rs
new file mode 100644
index 0000000..0003f7f
--- /dev/null
+++ b/src/vga_buffer.rs
@@ -0,0 +1,138 @@
+use core::ptr::Unique;
+use core::fmt::Write;
+use spin::Mutex;
+
+#[allow(dead_code)]
+#[repr(u8)]
+pub enum Color {
+	Black        = 0,
+	Blue         = 1,
+	Green				 = 2,
+	Cyan				 = 3,
+	Red          = 4,
+	Magenta      = 5,
+	Brown        = 6,
+  LightGray		 = 7,
+	DarkGray		 = 8,
+	LightBlue		 = 9,
+	LightGreen   = 10,
+	LightCyan		 = 11,
+	LightRed     = 12,
+  Pink         = 13,
+  Yellow       = 14,
+  White        = 15,
+}
+
+#[derive(Clone, Copy)]
+struct ColorCode(u8);
+
+impl ColorCode {
+	const fn new(foreground: Color, background: Color) -> ColorCode {
+		ColorCode((background as u8) << 4 | (foreground as u8))
+	}
+}
+
+#[repr(C)]
+#[derive(Clone, Copy)]
+struct ScreenChar {
+	ascii_character: u8,
+	color_code: ColorCode,
+}
+
+const BUFFER_HEIGHT: usize = 25;
+const BUFFER_WIDTH: usize = 80;
+
+struct Buffer {
+	chars: [[ScreenChar; BUFFER_WIDTH]; BUFFER_HEIGHT],
+}
+
+pub struct Writer {
+	column_position: usize,
+	color_code: ColorCode,
+	buffer: Unique<Buffer>,
+}
+
+impl Writer {
+	pub fn write_byte(&mut self, byte: u8) {
+		match byte {
+			b'\n' => self.new_line(),
+			byte => {
+				if self.column_position >= BUFFER_WIDTH {
+					self.new_line();
+				}
+
+				let row = BUFFER_HEIGHT - 1;
+				let col = self.column_position;
+
+				self.buffer().chars[row][col] = ScreenChar {
+					ascii_character: byte,
+					color_code: self.color_code,
+				};
+				self.column_position += 1;
+			}
+		}
+	}
+
+	pub fn write_str(&mut self, s: &str) {
+		for byte in s.bytes() {
+			self.write_byte(byte);
+		}
+	}
+
+	fn buffer(&mut self) -> &mut Buffer {
+		unsafe { self.buffer.get_mut() }
+	}
+
+	fn new_line(&mut self) {
+		for row in 0..(BUFFER_HEIGHT-1) {
+			let buffer = self.buffer();
+			buffer.chars[row] = buffer.chars[row + 1]
+		}
+
+		self.clear_row(BUFFER_HEIGHT - 1);
+		self.column_position = 0;
+	}
+
+	fn clear_row(&mut self, row: usize) {
+		let blank = ScreenChar {
+			ascii_character: b' ',
+			color_code: self.color_code,
+		};
+
+		self.buffer().chars[row] = [blank; BUFFER_WIDTH];
+	}
+}
+
+impl ::core::fmt::Write for Writer {
+	fn write_str(&mut self, s: &str) -> ::core::fmt::Result {
+		for byte in s.bytes() {
+			self.write_byte(byte)
+		}
+		Ok(())
+	}
+}
+
+pub static WRITER: Mutex<Writer> = Mutex::new(Writer {
+	column_position: 0,
+	color_code: ColorCode::new(Color::LightCyan, Color::Black),
+	buffer: unsafe { Unique::new(0xb8000 as *mut _) },
+});
+
+macro_rules! print {
+	($($arg:tt)*) => ({
+		use core::fmt::Write;
+		let mut writer = $crate::vga_buffer::WRITER.lock();
+		writer.write_fmt(format_args!($($arg)*)).unwrap();
+	});
+}
+
+macro_rules! println {
+	($fmt:expr) => (print!(concat!($fmt, "\n")));
+	($fmt:expr, $($arg:tt)*) => (print!(concat!($fmt, "\n"), $($arg)*));
+}
+
+pub fn clear_screen() {
+	for _ in 0..BUFFER_HEIGHT {
+		println!("");
+	}
+}