Object - A programming unit that groups together a data structure instance variables and the operations methods that can use or affect that data. Objects are the principal building blocks of object-oriented programs. primary key An attribute in an entity that uniquely identifies rows of that entity. For example, the Employee entity can contain an EmpID attribute that uniquely identifies each employee.

Odd Parity - An error-checking system in which the sending device adds an extra bit set to 0 or 1 as necessary to make the total of 1 bits add up to an odd number. The receiving device adds the 1 bits and if the total is an odd number, it assumes the message came through intact.

Off-Hook - When a modem goes off-hook, it claims the telephone line to which it is connected. Taking a modem off-hook is equivalent to picking up a telephone to make or answer a call.

Offline Edit - The creative edit, where edit decisions are made. When the offline edit is finished, the material is often recaptured at high quality or an EDL is generated for re-creating the edit on another system.

OMF - Acronym for Open Media Format. An audio file format, supported by many Digital Audio Workstations, that allows all of the audio and edit points in an audio sequence to be exported as a self-contained file. OMF files are often given to an audio post-production facility, finished there, and then used as the final audio in a feature.

On-Hook - When a modem goes on-hook, it releases the telephone line to which it is connected, freeing the telephone line for other uses. This action, which is equivalent to hanging up a telephone, terminates the current data connection.

Online Edit - The final editing process, where all the decisions made in the offline edit are applied to the original camera negative or full-resolution video reels.

On-Line Mode - In on-line mode, data sent from the computer to the modem is transmitted to the remote modem, instead of being interpreted as AT commands. When you establish a connection with another modem, the modem is automatically placed in on-line mode.

On-Line - The condition of a device being connected or of data being accessible to the computer.

Open Architecture - A computer that has an open-lid policy it invites add-on devices.

Open Directory
- The Apple directory services architecture, which can access authoritative information about users and network resources from directory domains that use LDAP, NetInfo, or Active Directory protocols; BSD configuration files; and network services.

Open Firmware - Open Firmware is a cross-platform firmware standard for controlling hardware and is used by all PCI-based Mac OS computers. You can start up in Open Firmware when troubleshooting.

Open Relay - A server that receives and automatically forwards mail to another server. Junk mail senders exploit open relay servers to avoid having their own mail servers blacklisted as sources of spam. Also known as relay point.

Open Source - A definition of software that includes freely available access to source code, redistribution, modification, and derived works. The full definition is available at www.opensource.org.

Open Systems Interconnection OSI Model - A reference model for describing network protocols and devices by the International Standards Organization ISO. This model divides protocols into seven layers to standardize and simplify protocol definitions.

OpenGL-OpenGL enables the computer to display accelerated three-dimensional graphics using applications designed to take advantage of OpenGL, including graphics cards with RAGE II, RAGE Pro, RAGE 128 and Radeon based video 2D and 3D graphics APIs application program interfaces.

Operating System - An application that, among other things, controls the way information is loaded into memory, the way the computer works with the information, the way information is stored on a disk, and the way the computer communicates with a printer and other peripheral devices. ProDOS, DOS 3.3, and Pascal are three operating systems available for the Apple IIgs.

Optical List - A film list Cinema Tools users can export for the optical house to use in printing effects for film. The optical list describes transition and motion effects that you created in your digital edit.

Optical Printer - Rephotographs one or more film elements onto a new section of film. An optical printer can add or delete light from an image, create superimposed effects, or make scene transitions such as wipes, fades, and dissolves.

Opticals - Effects produced by an optical printer, including transitions and superimposed titles. See also optical printer.

Option Key - A key on the Apple IIgs keyboard that, when pressed in conjunction with another key, creates a special effect. On other models of the Apple II, this key is labeled Apple.

ORBS - Open Relay Behavior-modification System-An Internet service that blacklists mail servers known to be or suspected of being open relays for senders of junk mail. ORBS servers are also known as black-hole servers.

Original Camera Negative - The negatives from the film shoot; the original source film. The original camera negative is what the negative cutter cuts after all the edits have been finalized in the digital editing system. There is only one original camera negative. Duplicate negatives can be made, but they are expensive. Also known as OCN.

OS - Operating system.

Output - Information traveling out of the computer.

Owner - The person who created a file or folder and who therefore has the ability to assign access privileges for other users. The owner of an item automatically has read and write privileges for an item. An owner can also transfer ownership of an item to another user.