Main » TERM » C »

COM

(1) In DOS systems, the name of a serial communications port. DOS supports four serial ports: COM1, COM2, COM3, and COM4. However, most software uses system interrupts to access the serial ports, and there are only two IRQ lines reserved. This means that the four COM ports share the same two IRQ lines. Typically, COM1 and COM3 use IRQ4, while COM2 and COM4 use IRQ3. So in general, if you have two devices, one of which is attached to COM1 and the other to COM3, you cannot use them simultaneously.

Also see the list of IRQ numbers in the Quick Reference section of Webopedia.

(2) Abbreviation of Component Object Model.







TECH RESOURCES FROM OUR PARTNERS
LATEST ARTICLES
Facts about Cloud Computing in 2017

The following facts and statistics capture the changing landscape of cloud computing and how service providers and customers are keeping up with... Read More »

Facts about Computer Science: Education and Jobs

The following computer science facts and statistics provide a quick introduction to the changing trends in education and related careers. Read More »

Text Messaging & Chat Abbreviations

From A3 to LOL and ZZZ this guide lists 1,500 text message and online chat abbreviations to help you translate and understand today's texting... Read More »

STUDY GUIDES
The Five Generations of Computers

Learn about each of the five generations of computers and major technology developments that have led to the computing devices that we use... Read More »

Computer Architecture Study Guide

Computer architecture provides an introduction to system design basics for most computer science students. Read More »

Network Fundamentals Study Guide

Networking fundamentals teaches the building blocks of modern network design. Learn different types of networks, concepts, architecture and... Read More »