| A/D | Analog To Digital | - | Human Genome |
| A/V | Audio/Visual | - | Human Genome |
| AAC | Advanced Audio Coding | - | Human Genome |
| AARP | AppleTalk Address Resolution Protocol | - | Human Genome |
| ABBH | Average Bouncing Busy Hour | - | Human Genome |
| ABC | Atanasoff-Berry Computer | - | Human Genome |
| ABEND | Abnormal End | - | Human Genome |
| AC | Alternating Current | - | Human Genome |
| ACD | Automatic Call Distributor | - | Human Genome |
| ACES | Asia Cellular Satellite System | - | Human Genome |
| ACK | Acknowledge Character | - | Human Genome |
| ACL | Access Control List | - | Human Genome |
| ACM | Association For Computing Machinery | - | Human Genome |
| ACPI | Advanced Configuration And Power Interface | - | Human Genome |
| ACTA | America's Carriers Telecommunications Association | - | Human Genome |
| ACU | Automatic Calling Unit | - | Human Genome |
| ADB | Apple Desktop Bus | - | Human Genome |
| ADCCP | Advanced Data Communications Control Protocol | - | Human Genome |
| ADO | ActiveX Data Objects | - | Human Genome |
| ADP | Automatic Data Processing | - | Human Genome |
| ADPCM | Adaptive Differential Pulse Code Modulation | - | Human Genome |
| ADS | Alternate Data Streams | - | Human Genome |
| ADSL | Asymmetric Digital Subscriber Line | - | Human Genome |
| ADVEIS | Anti-Virus Dependent Vulnerabilities In E-mail Infrastructure Security | - | Human Genome |
| AES | Asynchronous Event Scheduler | - | Human Genome |
| AFAIK | As Far As I Know | - | Human Genome |
| AGP | Accelerated Graphics Port | - | Human Genome |
| AH | Authentication Header | - | Human Genome |
| AI | Artificial Intelligence | - | Human Genome |
| AIFF | Audio Interchange File Format | - | Human Genome |
| AIFF-C | Audio Interchange File Format | - | Human Genome |
| AIML | Astronomical Instrument Markup Language | - | Human Genome |
| AIX | Advanced Interactive Executive | - | Human Genome |
| ALGOL | Algorithmic Language | - | Human Genome |
| ALU | Arithmetic (and) Logic Unit | - | Human Genome |
| AMANDA | Advanced Maryland Automatic Network Disk Archiver | - | Human Genome |
| AMD | Advanced Micro Devices | - | Human Genome |
| AML | Astronomy Markup Language | - | Human Genome |
| AMP | Advanced Metal Powder | - | Human Genome |
| AMPS | Advanced Mobile Phone System | - | Human Genome |
| AMS | American Mobile Satellite Corporation | - | Human Genome |
| AN | Active Network | - | Human Genome |
| ANSA | Adaptive Network Security Alliance | - | Human Genome |
| ANSI | American National Standards Institute | - | Human Genome |
| AOL | America Online | - | Human Genome |
| APA | All Points Addressable | - | Human Genome |
| API | Application Program(ming) Interface | - | Human Genome |
| APM | Advanced Power Management | - | Human Genome |
| APP | Application Portability Profile | - | Human Genome |
| APWG | Anti-Phishing Working Group | - | Human Genome |
| ARLL | Advanced Run Length Limited | - | Human Genome |
| ARM | Advanced (Acorn) RISC Machine | - | Human Genome |
| ARM | Advanced RISC Machines Ltd | - | Human Genome |
| ARP | Address Resolution Protocol | - | Human Genome |
| ARPA | Advanced Research Projects Agency | - | Human Genome |
| ARQ | Automatic Repeat Request | - | Human Genome |
| ASAP | Activate Secure Authentication Protocol | - | Human Genome |
| ASAP | As Soon As Possible | - | Human Genome |
| ASCII | American Standard Code For Information Interchange | - | Human Genome |
| ASF | ActiveMovie Streaming Format | - | Human Genome |
| ASIC | Application-Specific Integrated Circuit | - | Human Genome |
| ASP | Active Server Pages | - | Human Genome |
| ASP | Application Service Provider | - | Human Genome |
| ASP | Association Of Shareware Professionals | - | Human Genome |
| AT | Attention | - | Human Genome |
| ATA | AT Attachment | - | Human Genome |
| ATL | Active (ActiveX) Template Library | - | Human Genome |
| ATM | Asynchronous Transfer Mode | - | Human Genome |
| AUI | Attachment Unit Interface | - | Human Genome |
| AVI | Audio/Video Interleaved Format | - | Human Genome |
| AWHFY | Are We Having Fun Yet | - | Human Genome |
| AWT | Abstract Windows Toolkit | - | Human Genome |
| A-CSIRT | AT&T-Computer Security Incident Response Team
| - | Human Genome |
| AAA | administration, authorization, and authentication
| - | Human Genome |
| AAL | ATM adaptation layer
| - | Human Genome |
| AAN | application aware network
| - | Human Genome |
| AATOS | Alternative Access to Operator Services
| - | Human Genome |
| ABR | available bit rate
| - | Human Genome |
| ACO | Administrative Contracting Officer
| - | Human Genome |
| ACP | action control point
| - | Human Genome |
| ACR | anonymous call rejection
| - | Human Genome |
| ACS | Audio Conferencing Services
| - | Human Genome |
| ACT | accounting control transaction
| - | Human Genome |
| ADM | asynchronous disconnected mode
| - | Human Genome |
| ADR | alternate destination routing
| - | Human Genome |
| AERS | alternate enhanced redirect solutions
| - | Human Genome |
| AGC | Automatic Gain Control
| - | Human Genome |
| AGMEMS | AT&T Government Markets Enterprise ManagementSystem
| - | Human Genome |
| AGN | AT&T Global Network
| - | Human Genome |
| AGS | AT&T Government Solutions
| - | Human Genome |
| AGSEMC | AT&T Government Solutions Enterprise ManagementCenter
| - | Human Genome |
| AHC | agency hierarchy code
| - | Human Genome |
| AHS | Application Hosting Services
| - | Human Genome |
| AIOD | automatic identification of outward dialing
| - | Human Genome |
| AIS | automated information system
| - | Human Genome |
| ALC | agency local contact
| - | Human Genome |
| ALDS | Applications Layer Data Service
| - | Human Genome |
| ALG | application layer gateway
| - | Human Genome |
| ALNP | aggregated line and node protection
| - | Human Genome |
| AMI | alternate mark inversion
| - | Human Genome |
