Tiny operating system kernel for education purposes

The operating systems courses are often organized according to three basic approaches: as user-centric, theoretically oriented with the explanation of the principles of operation, or through analysis and modification of the kernel source code. While the third approach is the most illustrative, it requires the most of the time at the expense of broader analysis of implementation for different algorithms of the operating systems. Hence, the frequent approach is the development of small kernel, instead of analysing those that are in wider use. In this paper we will present a simple kernel, with a minimal size of source code, which can be fully described in 90 minutes of classroom teaching, but still large enough to be installed and started on a typical PC. This educational version of a kernel includes the basic functions of any OS core: video, keyboard, disk, file system, memory, processes and threads.