General: Write basic README

README.md

@@ -1,2 +1,45 @@
 # banan-os
-My hobby operating system. Currently runs on x86 32 and 64 bit cpus.
+This is my hobby operating system written in C++. Currently runs on x86 based architectures (32 and 64 bit). Currently this operating system supports ext2 filesystem, ata drives (pio mode), vesa/vbe graphics mode and multithreaded processing.
+
+## Building
+> **_NOTE:_** I will be using ninja in these build instructions but you may use any other buildsystem cmake supports. If you want to use ninja, you can either define a environment variable 'CMAKE_GENERATOR=Ninja' or pass '-G Ninja' to all commands invoking cmake.
+
+Create the build directory and cofigure cmake
+```sh
+mkdir build
+cd build
+cmake ..
+```
+
+ 
+
+> **_NOTE:_** The following step has to be done only once. This might take a long time since we are compiling binutils and gcc.
+
+To build the toolchain for this os. You can run the following command.
+```sh
+ninja toolchain
+cmake --fresh .. # We need to reconfigure cmake to use the new compiler
+```
+
+ 
+
+To build the os itself you can run either of the following commands. You will need root access since we need to mount the disk image to install grub.
+```sh
+ninja qemu
+ninja bochs
+```
+
+ 
+
+You can also build the kernel or disk image without running it:
+```sh
+ninja kernel
+ninja image
+```
+
+ 
+
+If you have corrupted your disk image or want to create new one, you can either manually delete _banan-os.img_ and cmake will automatically create you a new one or you can run the following command.
+```sh
+ninja image-full
+```