How to Make an Operating System

This text will teach the basics of what is needed to create a basic operating system. Recommended for advanced users.

Things You'll Need

• A programming tool with compiler.
• A spare computer to test your new operating system.

Instructions

1. First, you must develop your control programs. These are what control and maintain your computer. The program must be in the form of firmware (loaded into the ROM, so a user can't accidentally delete an important file.) This will generally be classified as an initial program loader. An example of how this should work (chain of events, not actual code): Turn Computer On >> Memory chips are automatically activated >> The Initial Program Loader should read a boot sector routine (located in primary memory).

2. Congratulations, your OS will now read a few things. Can't have input, so let's fix that. You'll need some support control programs, such as a linkage editor, and a Input/Output Control System.

3. Lastly, add the utility programs. These are programs like MS-DOS's FDisk, FORMAT, ATRRIB, FIND, etc...
   And you're done! It's not exceedingly difficult IF you know what you're coding.

Tips & Warnings

• If you get lost, I'd suggest looking at some example/open source code. A decent Windowsesque one I found is here: http://www.reactos.org/en/index.html

• Keep your code organized.

• If you're going to use it, and take it for a drive over the net, be careful. Running an OS that's very similar to current major OS will often lead to poor security, letting even mere script-kiddies gobble up sensitive information.