O

OC (optical carrier)

OCR (optical character recognition)

OD (overdrive)

ODI (Open Data-link Interface)

OEM (original equipment manufacturer)

OLE (object linking and embedding)

OLGA (organic land grid array)

OS (operating system)

OSI (open systems interconnection)

OSO (overscan operation)

OSTA (Optical Storage Technology Association)

OTP (one-time programmable)

OTP (opposite track path)