Abstract:
NeXT -> OPenStep -> Yellow Box ->Cocoa
Keywords:
1.NeXT
NeXT Inc. was a company founded by Steve Jobs, etc. from 1986 until 1997 when NeXT merged with Apple.
2.OpenStep
an object-oriented API specification for a legacy object-oriented operating system, with the basic goal of offering a NeXTSTEP-like environment on a non-NeXTSTEP operating system.
3. Difference between OpenStep and NeXT
3.1 OpenStep no longer referenced to operating system.
3.2 OpenStep no longer depended on Mach kernal.
3.3 OpenStep was endian-free
3.4 number of new classes(NS) and functionality, Foundation Kit or Foundation, were provided to supporting endian-free and platform-independent.
3.5 OpenStep used [Reference Counting] to manage memory and object lifetime, and provided [Autorelease Pools] for automatic memory management
Detail:
----------- As an Entire Operating System
NeXTSTEP version 0.9 1988
NeXTSTEP version 1.0 1989
NeXTSTEP version 2.0 1990
NeXTSTEP version 3.0 1992
included [windowing an imaging system(based on Display PostScript)] [Mach kernal] [device drives], and so on.
the software libraries(dynamically shared) were known as Kits, not frameworks. Application Kit was the most prominent of them. Besides this, Sound Kit and Music Kit were also included.
----------- shipped to several architectures more than NeXT computer(Mach kernel)
NeXTSTEP version 3.1 1993 the OpenStep initiative also took form
OPENSTEP 1994 OpenStep compliant version of NeXTSTEP
OpenStep API 1994 Application Kit began to use the "NS" prefix. was splited from Foundation. became known as, simply, AppKit
OpenStep version 4.0 1996
----------- merged with Apple
Yellow Box 1997 Apple acquired NeXT, and renamed it as Yellow Box.
Cocoa Foundation + AppKit
Cocoa Touch Foundation + UIKit