One of the things that fascinates me about the history of the Newton is that if it weren't for complaints from those advocating C++ that escalated to John Sculley (who ruled in their favor), we may have ended up with mass-market machines that ran a Lisp operating system. There's a wonderful interview between lispm and Mikel Evins, two regular contributors on Hacker News, that can be found at http://lispm.de/lisp-based-newton-os.

I'm quite fascinated by pre-1997 Apple's projects. Before Jobs' return, Apple was an unfocused beacon of innovation; in its attempts to find a successor to the classic Mac OS, it explored various paths, but none of these paths led to a successor until Apple bought NeXT. Apple's more radical explorations during this era seem to have a profound Xerox PARC influence. Xerox PARC is probably most famous for Smalltalk and its GUI. However, there are many people who don't know that Xerox developed its own Lisp environment, Interlisp, which was known for its GUI (not all Lisp innovations came from MIT). These explorations ended once Apple committed to NeXT technology for its foundation in 1997, and today Apple has been pursuing its own direction (e.g., the iOS human interface guidelines, Swift, the gradual inclusion of iOS UI/UX elements and practices in macOS) that is distinct from the Xerox PARC, classic Macintosh, and NeXT traditions.