Description:

It is a library of graphical user interface classes written completely
in the Objective-C language; the classes are based upon the OpenStep
specification as release by NeXT Software, Inc. The library does not
completely conform to the specification and has been enhanced in a
number of ways to take advantage of the GNU system. These classes
include graphical objects such as buttons, text fields, popup lists,
browser lists, and windows; there are also many associated classes for
handling events, colors, fonts, pasteboards and images.