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.

Webopedia Staff
Webopedia Staff
Since 1995, more than 100 tech experts and researchers have kept Webopedia’s definitions, articles, and study guides up to date. For more information on current editorial staff, please visit our About page.
Get the Free Newsletter
Subscribe to Daily Tech Insider for top news, trends & analysis
This email address is invalid.
Get the Free Newsletter
Subscribe to Daily Tech Insider for top news, trends & analysis
This email address is invalid.

Related Articles

Embedded Analytics

Embedded analytics brings self-service business intelligence to everyday application users.

HRIS

Human resources information system (HRIS) solutions help businesses manage multiple facets of their workforce operations. They provide a central platform for human resources professionals...

Complete List of Cybersecurity Acronyms

Cybersecurity news and best practices are full of acronyms and abbreviations. Without understanding what each one means, it's difficult to comprehend the significance of...

Human Resources Management System

A Human Resources Management System (HRMS) is a software application that supports many functions of a company's Human Resources department, including benefits administration, payroll,...

ScalaHosting

ScalaHosting is a leading managed hosting provider that offers secure, scalable, and affordable...

HRIS

Human resources information system (HRIS) solutions help businesses manage multiple facets of their...

Best Managed Service Providers...

In today's business world, managed services are more critical than ever. They can...