(1) (
Instruction
Set
Architecture) See
instruction set.
(2) (
Industry
Standard
Architecture) An earlier bus system used in PCs. See
ISA bus.
(3) (
Interactive
Services
Association) See
Internet Alliance.
(4) See
internal security assessor.
(5) (International Society of Automation, RTP, NC) A trade association founded in 1945 that is dedicated to industrial control systems which includes measurement and instrumentation, robotics, motion control and process control. ISA supports ISA EXPO, the industry's premier trade show for more than 50 years as well as the Directory of Instrumentation.