Objective-C doesn't support multiple inheritance. A logical subdivision of a program within which all names must be unique. Symbols in one name space won't conflict with identically named symbols in another name space. NeXT also includes an application development and user environment, consisting of the Workspace Manager, the Window Server, Project Builder and Interface Builder, and other software. Nib files are created using Interface Builder and can contain archived objects, information about connections between objects, and sound and image data.
Objects are the principal building blocks of object-oriented programs.
Outlet instance variables are a way for an object to keep track of the other objects to which it may need to send messages. See also attention panel . The user can choose an item by dragging to it and releasing the mouse button. When the mouse button is released, the pop-up list disappears. A language, like C, that organizes a program as a set of procedures that have definite beginnings and ends.