- B8ZS Bipolar with 8 Zero Substitution
- BAPI Bridge Application Program Interface
- BASH Bourne Again SHell
- BASIC Beginners All-purpose Symbolic Instruction Code
- BB Bye Bye
- BBS Bulletin Board System / Bulletin Board Service
- BC Block Check
- bcc blind carbon copy
- BCD Binary Coded Decimal
- BCS Business Communication Services
- BDE Borland Database Engine
- BDOS Basic Disk Operating System
- BER Basic Encoding Rules
- BEV Blacksburg Electronic Village
- bg background
- BGP Border Gateway Protocol
- BHA ButtHead Astronomer
- BIC Borland International Conference
- BIND Berkeley Internet Name Domain
- BIOS Basic Input/Output System
- BIPS Billion Instructions Per Second
- BITNET Because Its Time NETwork
- BIU Basic Information Unit
- BIV Built-In Video
- BIX Byte Information EXchange
- BLOB Binary Large OBject
- BMUG Berkeley Macintosh Users Group
- BOC Bell Operating Company
- BOF Birds Of a Feather
- BOOTP BOOTstrap Protocol
- BPDU Bridge Protocol Data Unit
- BPR Business Process Re-engineering
- bps bits per second
- BPV BiPolar Violations
- BRI Basic Rate Interface
- BRS Bibliographic Retrieval Service
- BSC Binary Synchronous Communication
- BSD Berkeley Software Division
- BTB Branch Target Buffer
- BTU Basic Transmission Unit
- BTW By The Way
- BVD Battery Voltage Detect