O

object

A kind of information, such as words, paragraphs, and characters, that an application knows how to work with. An application’s AppleScript dictionary lists the kinds of objects it can work with under script control.

Open GL (Open Graphics Library)

An industry standard for three-dimensional graphics rendering. It provides a standard graphics API by which software and hardware manufacturers can build 3D applications and hardware across multiple platforms on a common standard.

open source

Typically refers to software developed as a public collaboration and made freely available.

operating system

Software that controls the basic activities of a computer system. Also known as system software.

original item

A file, folder, or disk to which an alias points, and which opens when you open its alias.

orphaned alias

An alias that has lost its link with its original item (and, therefore, Mac OS X cannot find it).

outline font

A font whose glyphs are outlined by curves and straight lines that can be smoothly enlarged or reduced to any size and then filled with dots.

owner

The user who can assign access privileges to a file or folder.