portable operating system for unix
portable operating system interface for computing systems
portable operating system interface
unix operating system unix
portable operating system
operating system for preventing electric mal-operation
OSDS Operating System for Distributed Switching
OSI Operating System Interface
operating system interface
GSM(Global System for Mobile) portable communication
portable operating table
standards for portable fire extinguishers
table for portable aspirator
16-bit operating system
alarm for operating condition
Android operating system