An anonymous reader writes "As part of his 1680-page book Mac OS X Internals: A Systems Approach, Amit Singh of kernelthread.com wrote a very detailed technical history of Apple's operating systems. Since he had to cut down on the history chapter because of the book's already too-large size, most of this chapter didn't make it to the printed book. Singh has made available the history chapter as a free PDF. The file is 140 pages long, and is generously filled with figures and screenshots. It starts with the internals of the original Apple I and goes through a tour of all operating systems Apple dabbled with, including internals of A/UX, Lisa OS, and such. It even covers details of outside influences like the Xerox Alto, STAR System, Smalltalk, and Sketchpad, and closer to home things like Mach, NeXTStep, and OpenStep."

NoviceW writes to share that there are plenty of interesting articles written about Mac OS X applications for switchers, but not many guides focused on programmers switching from other operating systems. This guide lists a few of the more prominent tools for Mac developers, what other tools can't you do without?

MacHore writes "0xFE has an excellent tutorial on Mach-O, which is the file format used by OS X executable files and libraries. It goes into great detail about how Mach-O works, and explains what OS X actually does when it loads and runs an application. Subtopics include Universal Binaries, The Dynamic Linker, Using otool, and other goodies."