Reverse-engineering the BIOS allowed third parties to democratize hardware.

Given copyright laws, this article does not provide direct pirated links. However, here are the for obtaining an updated digital copy:

To understand why this textbook remains relevant, one must understand the unique historical pivot point it documents: the transition from a proprietary IBM ecosystem to an open market of "clones." The Original IBM PC (1981)

, the book was born during a pivotal era when the "IBM Clone" market was exploding. While IBM established the standard with the 1981 release of the Model 5150, its open architecture allowed third-party manufacturers to create compatible machines (clones), making personal computing affordable for the masses. Google Books