Object

In object-oriented programming, a data item with instructions for the operations to be performed on it.

Object Programming

A style of programming where you bundle sets of instructions into packages known as objects.  Object-oriented programming squishes the instructions into self sufficient modules. 

OCR

Stands for Optical Character Recognition. Here's a more down
to earth explanation of it: a program that is used with scanners
or computer fax machines so when they scan or receive a fax
with letters and numbers, it will turn into editable text so you
can change it around, and it will have the same clear quality as
a regular document

OCX

OLE Custom Control
Microsoft developed the OCX standard as an advanced version of the VBX standard. Although the VBX standard is designed for 16-bit operating systems. OCX is designed for 32-bit operating systems.

OLE

Object linking and embedding. A way to transfer and share
information between applications.

Online

Hooked up to a specified computer, usually said of the printer when it's
connected to your PC and ready to print. Online also may refer to being
connected an an online service.

Online Service

An enormous computer 'mainframe' that a bunch of people connect
to at the same time. The things you can do on an online service are:
download shareware, freeware, and demos, chat with others live, use
eMail, get the news and the possibilities go on.

OOP

Stands for "Object Oriented Programming."

Operating System

The application that controls the computer.

Optical Fiber

A glass thread that serves as a basis for high speed, and reliable, 
data transmission.

Output Area

An area of memory where data is stored until it can be output; also called a buffer

Output Device

Output is what the computer spits out after it churns through the information you put into it. Output devices are what give us this output, and take form as speakers, printers, monitors, etc.

 Over-clocking

Setting the jumpers on your motherboard to "trick" your computer into
thinking that you have a faster processor than you really do. This can
lead to overheating. (Suggested by: YTCC Guru)

OverFlow

Memory overflow stops a computer dead in its tracks. Too many
characters equals overflow.