”This is a free minix-like kernel for i386(+) based AT-machines,” began the Linux version 0.01 release notes in September of 1991 for the first release of the Linux kernel. ”As the version number (0.01) suggests this is not a mature product. Currently only a subset of AT-hardware is supported (hard-disk, screen, keyboard and serial lines), and some of the system calls are not yet fully implemented (notably mount/umount aren’t even implemented).” Booting the original 0.01 Linux kernel required bootstrapping it with minix, and the keyboard driver was written in assembly and hard-wired for a Finnish keyboard. The listed features were mostly presented as a comparison to minix and included, efficiently using the 386 chip rather than the older 8088, use of system calls rather than message passing, a fully multithreaded FS, minimal task switching, and visible interrupts. Linus Torvalds noted, ”the guiding line when implementing linux was: get it working fast. I wanted the kernel simple, yet powerful enough to run most unix software.”

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