@Michael Ellis: There's a lot of Mac OS stuff running on top of it, like Carbon, etc. but the OS itself and the core frameworks are NeXTStep
I think the problem was the use of the word "just." It's ultimately a matter of perspective. Apple didn't start from scratch -- they used an established and solid base. However, Mac OS X is pretty far from where NeXT would have ended up on a linear path.
Foundation is based on CoreFoundation, Quartz/PDF is used instead of Display Postscript, QuickTime was added, and a completely different user experience was implemented. Those are pretty big changes. However, the basic concepts that OpenStep was based on are still present, along with much of the plumbing.
by Scott Stevenson — Mar 24
I think the problem was the use of the word "just." It's ultimately a matter of perspective. Apple didn't start from scratch -- they used an established and solid base. However, Mac OS X is pretty far from where NeXT would have ended up on a linear path.
Foundation is based on CoreFoundation, Quartz/PDF is used instead of Display Postscript, QuickTime was added, and a completely different user experience was implemented. Those are pretty big changes. However, the basic concepts that OpenStep was based on are still present, along with much of the plumbing.