How to Make a Computer Operating System.

How to Make a Computer Operating System.

Steps :-
1) Learn Programming before you begin. Assembly Language is vital, another supplementary low level language such as C is strongly
recommended .
2) Decide what media you want to load your OS on. It can be a CD drive, DVD drive, flash drive, a hard disk, or another PC.
3) Decide what you want your OS to do. Whether it is a fully capable OS with a graphical user interface (GUI) or something a bit more
minimalism, you'll need to know what direction you are taking it before beginning.
4) Target what processor platform your operating system will support. AI-32 and x86_64 are the two most common for personal
computers so they're your best bet.
5) Decide if you would rather do it all yourself from the ground up, or if there is an existing kernel you would like to build on top of.
Linux from Scratch is a project for those that would like to build their own Linux distro .
6) Decide if you're going to use your own bootloader or a pre-created one such as Grand Unified Bootloader (GRUB). While coding
your own bootloader will give a lot of knowledge of the hardware and the BIOS, it may set you back on the programming of the actual
kernel.
7) Decide what programming language to use. While it is possible to create an operating system in a language such as Pascal or
BASIC, you will be better off using C or Assembly. Assembly is absolutely necessary, as some vital parts of an operating system
require it. C++, on the other hand, contains keywords that need another fully-built OS to run.
--> In order to compile an operating system from C or C++ code, you will of course be using one compiler or another. You should
therefore read the user guide/manuals/documentation for your chosen C/C++ compiler, whether it comes packaged with the software
or is available on the distributor's website. You will need to know many intricate things about your compiler and, for C++
development, you should know about the compiler's mangling scheme and its ABI. You are expected to understand the various
executable formats (ELF, PE, COFF, plain binary, etc.), and understand that the Windows proprietary format, PE (.exe), has been
copyrighted.
Decide on your application programming interface (API). One good API to choose is POSIX, which is well documented. All Unix
systems have at least partial support for POSIX, so it would be trivial to port Unix programs to your OS.
9) Decide on your design. There are monolithic kernels and microkernels. Monolithic kernels implement all the services in the kernel,
while microkernels have a small kernel combined with user daemons implementing services. In general, monolithic kernels are
faster, but microkernels have better fault isolation and reliability.
10) Consider developing working in a team. That way, less time is required to solve more problems, producing a better OS.
11) Do not wipe your hard drive completely. Remember, wiping your drive will clear out all your data and is irreversible! Use GRUB or
another boot manager to dual-boot your system with another OS until yours is fully functional.
12) Start small. Begin with small things such as displaying text and interrupts before moving on to things such as memory
management and multitasking.
13) Keep a backup of the last working source. In case something goes terribly wrong with the current version or your development PC
crashes and is unable to boot, it is an excellent idea to have a second copy to work with/troubleshoot.
14) Consider testing your new operating system with a virtual machine. Rather than rebooting your computer each time you make
changes or having to transfer the files from your development computer to your test machine, you use a virtual machine application to
run your OS while your current OS is still running. VM applications include VMWare (which also has a freely available server
product), the open-source alternative Bochs, Microsoft Virtual PC (not compatible with Linux), and xVM VirtualBox.
15) Release a "release candidate." This will allow users to tell you about potential problems with your operating system.
16) An operating system can be user friendly too.
Important Notice :-
Do not start an operating system project in order to begin learning programming. If you don't already know C, C++, Pascal, or some
other suitable language inside out, including pointer manipulation, low-level bit manipulation, bit shifting, inline assembly language,
etc., you are not ready for operating-system development.