ActiveX - ActiveX is a brand name referring to a set of Microsoft's technologies and services based on COM (Component Object Model) widely released in 1997.

Active Channel - An Active Channel is a frequently updated information residing on a Web server.

ADN - (Advanced Digital Network)

Address - Unique identifier of a web page. URL (Uniformed Resource Locator) is more frequently used for this purpose.

Ajax - Ajax (Asynchronous JavaScript and XML)

ADO - ActiveX Data Objects

ADSL - (Asymmetric Digital Subscriber Loop)

AIFF - Audio Interchange File Format

Anon FTP - Anonymous FTP (Anon FTP)

Anonymous remailer - Anonymous remailer

Anonymous FTP (Anon FTP) - Anonymous FTP (Anon FTP)

Anonymous remailer - Anonymous remailer

ANSI - ANSI

Apache - Apache

Archie - Archie

Archive - Archive

Archive site - Archive site

ARJ - ARJ

ARPA - ARPA

ARPAnet - ARPAnet

ASCII - ASCII

ASP - ASP

Asynchronous Transfer Mode (ATM) - Asynchronous Transfer Mode (ATM)

Attachment - Attachment

AU - AU

Authentication - Authentication

AVI - AVI