The first documentation for the original 1984 Macintosh was available only in the form of photocopied sheets that could be obtained from Apple. A "telephone-book" version of Inside Macintosh was also available, which consisted of one 1000 page volume. It was sent as a promotional copy to developers. The 1000 page manual was sent out because the "real" version would take some time to print. In 1985, they were published by Addison-Wesley in the form of a hardcover book that was available to the general public. The first version had three volumes, which covered the original Mac 128K, Macintosh XL, and the Mac 512K ("Fat Mac") models. When the Macintosh Plus was released, a fourth volume was added, detailing the changes to the system software introduced with that model. A further "delta" manual, volume 5, was introduced with the Mac II line in 1987. This manual discusses color QuickDraw, as well as the Mac II and Mac SE hardware and other new software components.
By the time of System 7, released in 1991, the Inside Macintosh "delta" model was becoming seriously stretched. Nevertheless the details of System 7 were documented in the immense Volume VI.
Shortly after this, Apple revamped the entire Inside Macintosh series, breaking it into volumes according to the functional area discussed, rather than specific machine models or capabilities. In this form, the series was far more coherent and a much better reference for programmers. As new functionality was added to the Mac OS, a new volume could be written without invalidating those published earlier, in contrast to the first series, which became increasingly out of date over time.
In the late 1990s, Apple ceased to publish Inside Macintosh as a printed book, instead making it available as a CD-ROM, and online. Since then, the CD variant has been phased out, though Apple developers can still receive online documentation as part of the developer CDs. In its online form, the information is much easier to maintain, but some developers still prefer a printed format.
Inside Macintosh only covers the 'Classic' Mac OS; a new set of documentation was introduced for OS X. Initially this documentation included only the 'Carbon Specification' that said which APIs were supported in Carbon and which were not, and the Cocoa documentation inherited from OPENSTEP. Later, the Carbon Specification was refactored into the Carbon Reference, which actually described the APIs it documented (taking much content from Inside Macintosh). Today, the Carbon Reference and Cocoa reference are bundled together in the ADC Reference Library.
Bruce F. Webster in BYTE in December 1985 described Inside Macintosh as "infamous, expensive, and obscure", but "for anyone wanting to do much with the Mac ... the only real [printed] source of information". He quoted Kathe Spracklen, developer of Sargon, as saying that the book "consists of 25 chapters, each of which requires that you understand the other 24 before reading it".
- Webster, Bruce (1985-12). "Microcomputer Color Graphics-Observations". BYTE. p. 405. Retrieved 28 October 2013.