What Does DB-9 Mean?

DB-9 is an analog 9-pin plug of the D-sub miniature (D-sub) connector plug and socket family for computer and communication devices. Some uses and characteristics of the DB-9 connector are:

  • Serial communication
  • Token Ring network adapters
  • IBM video interfaces
  • Asynchronous data transfer (standardized as RS-232C)

This term was originally known as DE-9.

Techopedia Explains DB-9

DB-9 connectors are built with the fewest pins and holes in the D-sub connector family. At one time, DB-9 was the typical computer and server component designed to work with the EIA/TIA 232 serial interface, which established the 9-pin function as a standard. The original DB-9 connectors were used for serial peripheral devices such as keyboards, mice and joysticks. Modern DB-9s include interfaces such as USB, PS/2 and FireWire.


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…