Infrared Data Association
1. A standard for transmitting data, originally designed for use with infrared (non-visible) light technology.
IrDA, together with infrared, was used to wirelessly connect the phone to various devices, to exchange information such as phone book entries with other phones. Finally, some phones can also use it to send information such as phone book entries and calendar events to Infrared-equipped printers.
IrDA over infrared was essentially replaced by Bluetooth, which has a longer range and does not require line-of-sight since it uses radio waves instead of light.
Infrared was once common in laptop computers, but is almost unheard of now. Computers without infrared required a USB infrared adapter to communicate with a phone via infrared.
2. The industry group that created the IrDA technical standard.