PID

PID may refer to:

Medicine

• Prolapsed intervertebral disc, commonly called a "herniated disc"
• Primary immune deficiency, disorders in which part of the body's immune system is missing or does not function properly
• Pelvic Inflammatory Disease, (or Pelvic Inflammatory Disorder), an infection and inflammation of the female uterus, fallopian tubes, and/or ovaries

Business

• Project Initiation Document, all major aspects of the project and forms the basis for its management and the assessment of overall success

Technology

• Photoionization detector, measures volatile organic compounds and other gases
• Process identifier, a number used by Unix kernels and Windows operating systems to identify a process
• PID controller, a control concept used in automation. (Proportional/Integral/Derivative)
• Piping and instrumentation diagram, a technical diagram showing all (or a part of) pipelines, instruments, valves, etc., of a process plant
• Process and instrumentation diagram, commonly used in chemical and process engineering
• Passive Infrared Detector, a PIR-based motion detector
• Personal Integrating/Indicating Dosemeter, a type of dosimeter for personal use
• Packet Identifier, a field in a MPEG transport stream packet.
• Packet ID, used to identify audio/video streams in DVB "Digital Video Broadcasting"
• Physical Interface Device, a class of USB devices.

Organizations

• Police Intelligence Department, a staff department of the Singapore Police Force
• Political Intelligence Department, a British clandestine body created to produce and disseminate propaganda during WWII.

Other

• Pathways Into Darkness, a 1993 video game by Bungie Studios
• Parameter ID, in automotive repair, PIDs are requests for data through an OBD connector
• Paul Is Dead, a 1960s urban legend that Paul McCartney was dead
• Principal ideal domain, in abstract algebra, an integral domain in which every ideal is principal