Hello Everybody,
I've released a free book under the title "A Journey in Creating an Operating System Kernel: The 539kernel Book" which teaches the reader how to create an operating system's kernel called 539kernel. The reader will learn how to implement multitasking, paging and a filesystem through this book. 539kernel is a simple x86 32bit educational kernel which has been written especially for this book.
The book is available here:
https://539kernel.com/ you can read it online or as a PDF.
Regards.