object signing - technology that allows software developers to sign Java code, JavaScript scripts, or any kind of file, and that allows users to identify the signers and control access by signed code to local system resources.

object-signing certificate - certificate whose corresponding private key is used to sign objects such as code files.

offline - Not online. Not connected to the computer and turned on or not connected to a computer network.

OLE {oh-lay} [object linking and embedding] - A complex specification that allows embedding objects created by one application within documents created by another, and linking of documents between two applications.

online [on-line] - 1. Connected to the Internet or other online service that demands the use of a modem by the user; or, referring to a user who has an account which gives access to the Internet or other online service. 2. Connected to the computer (said of peripherals) 3. Connected to a computer network.

online service - A computer network accessed by modem. Online services generally charge a monthly fee, and offer such services as e-mail, information services, online shopping, news, games. Some examples are Prodigy, America Online, and CompuServe.

open - To prepare to read or write a file.

operating system - Master control program that translates the user's commands and allows application programs to interact with the computer's hardware.

optical mouse - A mouse that senses where it is by emitting a light that bounces off a special reflective mouse pad.

optical zoom - A type of zoom on digital cameras that replicates what a 35mm zoom does, by actually magnifying the subject of the photo using a lens. The optical zoom lens produces a better quality image than the alternative digital zoom.

optimization - A series of operations that can be performed periodically to keep a computer in optimum shape. Optimization is done by running a maintenance check, scanning for viruses, and defragmenting the hard disk.

option - [flag, switch, option switch] - An argument to a command that modifies its function rather than providing data. Options generally start with "/" in DOS. This is usually followed by a single letter or occasionally a digit.

output - information which flows out of a computer.

output device - A peripheral through which information from the computer is communicated to the outside world; for example, a display screen, printer, or speakers.