AA—Anti-Aliasing
AAA—Authentication Authorization, Accounting
AABB—Axis Aligned Bounding Box
AAC—Advanced Audio Coding
AAL—ATM Adaptation Layer
AALC—ATM Adaptation Layer Connection
AARP—AppleTalk Address Resolution Protocol
ABCL—Actor-Based Concurrent Language
ABI—Application Binary Interface
ABM—Asynchronous Balanced Mode
ABR—Area Border Router
ABR—Auto Baud-Rate detection
ABR—Available Bitrate
ABR—Average Bitrate
AC—Acoustic Coupler
AC—Alternating Current
ACD—Automatic Call Distributor
ACE—Advanced Computing Environment
ACID—Atomicity Consistency Isolation Durability
ACK—ACKnowledgement
ACK—Amsterdam Compiler Kit
ACL—Access Control List
ACL—Active Current Loop
ACM—Association for Computing Machinery
ALUA—Asymmetric Logic Unit Access
ACME—Automated Classification of Medical Entities
ACP—Airline Control Program
ACPI—Advanced Configuration and Power Interface
ACR—Allowed Cell Rate
ACR—Attenuation to Crosstalk Ratio
AD—Active Directory
AD—Administrative Domain
ADC—Analog-to-Digital Converter
ADC—Apple Display Connector
ADB—Apple Desktop Bus
ADCCP—Advanced Data Communications Control Procedures
ADO—ActiveX Data Objects
ADSL—Asymmetric Digital Subscriber Line
ADT—Abstract Data Type
AE—Adaptive Equalizer
AES—Advanced Encryption Standard
AF—Anisotropic Filtering
AFP—Apple Filing Protocol
AGP—Accelerated Graphics Port
AH—Active Hub
AI—Artificial Intelligence
AIX—Advanced Interactive eXecutive
Ajax—Asynchronous JavaScript and XML
AL—Active Link
AL—Access List
ALAC—Apple Lossless Audio Codec
ALGOL—Algorithmic Language
ALSA—Advanced Linux Sound Architecture
ALU—Arithmetic and Logical Unit
AM—Active Matrix
AM—Access Method
AM—Active Monitor
AM—Allied Mastercomputer
AM—Amplitude Modulation
AMD—Advanced Micro Devices
AMQP—Advanced Message Queuing Protocol
AMR—Audio Modem Riser
ANN—Artificial Neural Network
ANSI—American National Standards Institute
ANT—Another Neat Tool
AoE—ATA over