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Introduction
Dennis Ritchie at AT&T Bell Laboratories pioneered the C programming language in
the early 1970s. However, this programming language did not begin to gain widespread
popularity and support until the late 1970s.This was because, until that time, C compilers
were not readily available for commercial use outside of Bell Laboratories. Initially, this
growth in popularity was also partly spurred by the equal, if not faster, growth in popular-
ity of the UNIX operating system, which was written almost entirely in C.
Brad J. Cox designed the Objective-C language in the early 1980s.The language was
based on a language called SmallTalk-80. Objective-C was layered on top of the C lan-
guage, meaning that extensions were added to C to create a new programming language
that enabled objects to be created and manipulated.
NeXT Software licensed the Objective-C language in 1988 and developed its libraries
and a development environment called NEXTSTEP. In 1992, Objective-C support was
added to the Free Software Foundation’s GNU development environment.The copy-
rights for all Free Software Foundation (FSF) products are owned by the FSF. It is released
under the GNU General Public License.
In 1994, NeXT Computer and Sun Microsystems released a standardized specification
of the NEXTSTEP system, called OPENSTEP.The Free Software Foundation’s imple-
mentation of OPENSTEP is called GNUStep.A Linux version, which also includes the
Linux kernel and the GNUStep development environment, is called, appropriately
enough, LinuxSTEP.
On December 20, 1996, Apple Computer announced that it was acquiring NeXT
Software, and the NEXTSTEP/OPENSTEP environment became the basis for the next
major release of Apple’s operating system, OS X.Apple’s version of this development en-
vironment was called Cocoa.With built-in support for the Objective-C language, cou-
pled with development tools such as Project Builder (or its successor Xcode) and
Interface Builder,Apple created a powerful development environment for application de-
velopment on Mac OS X.
In 2007,Apple released an update to the Objective-C language and labeled it
Objective-C 2.0.That version of the language formed the basis for the second edition of
the book.
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