Exploring the internals of Linux v0.01: Linux kernel is often mentioned as a overwhelmingly large open source software. As of this writing, the latest version is v6.5-rc5, which consists of 36M lines of code. However, the first version of Linux, v0.01 was pretty small. It consisted of only 10239 lines of code. Excluding comments and blank lines, it was only 8,670 lines. It's small enough to understand and is a good starting point to learn about the internals https://seiya.me/blog/reading-linux-v0.01