As a longtime NeXTSTEP user, I still remember the first time I perused the filesystem of Mac OS X 10.0 (Cheetah) in 2001. And I distinctly remember thinking to myself that Apple basically took NeXTSTEP and slapped their own window manager and app framework on it only. The filesystem and toolset was nearly identical, and I even found several config files (I don't remember which ones) that still had NeXTSTEP listed in the comments.
As I evolved to develop iOS apps in the 2010s, NSObject (NS=NeXTSTEP) continued to be a reminder of this same lineage.
As I evolved to develop iOS apps in the 2010s, NSObject (NS=NeXTSTEP) continued to be a reminder of this same lineage.