Infrared
(IR)
Infrared is a line-of-sight wireless technology that uses a beam of invisible light to transmit information. This means that the infrared ports of both devices must be nearby and aimed at each other for a connection to succeed.
Infrared is the same technology used in most remote controls for home A/V gear such as TVs. Some smartphones are capable of controlling home A/V gear via infrared. Software that mimics a universal remote control is required, which may be included, or may need to be purchased from a third party and downloaded to the phone.
In early smartphones, from 2001 to 2007, infrared was also used for two-way exchange of data between phones, or between phones and computers. The main standard for this was IrDA.
See: IrDA
This functionality was then replaced by Bluetooth, which uses radio waves instead of light. Bluetooth is faster, more reliable, and more versatile than IrDA.
See: Bluetooth
