Plug and Play

What Does Plug and Play Mean?

Plug and Play (PnP) is a technology that allows the operating system to detect and configure internal and external peripherals as well as most adapters. It has the ability to find and configure hardware components without having to reset DIP switches and jumpers. PnP also refers to hot swapping, or hot plugging, structures such as Firewire or USB sticks and other devices.


When booting a PC, PnP identifies the attached peripheral devices and regulates the proper internal settings by configuring the direct memory access (DMA), interrupt requests (IRQ) and input/output (I/O) addresses.

Techopedia Explains Plug and Play

Most modern devices have a PnP compatible BIOS. Newer systems such as Firewire and USB are intentionally constructed to support changes in configuration settings.

For PnP to function it requires support from software and hardware. The hardware uses an ID code, allowing it to be identified by the software. The ID code consists of either a four-bit code or larger bits containing names and serial numbers. Before the industry standard architecture (ISA) was introduced, PnP did not have an ID code and was not very dependable. IRQ lines and I/O addresses would be often be set incorrectly, causing malfunction. When the peripheral component interconnect bus was introduced, PnP was finally became dependable.


Related Terms

Latest Hardware Terms

Related Reading

Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…