The Infrared-HOWTO (former IR-HOWTO) provides an introduction to Linux and infrared devices and how to use the software provided by the Linux/IrDA project. This package uses IrDA(TM) compliant standards. IrDA(TM) is an industrial standard for infrared wireless communication, and most laptops made after January 1996 are equipped with an IrDA(TM) compliant infrared transceiver. Infrared ports let you communicate with printers, modems, fax machines, LANs, and other laptops. Speed ranges from 2400bps to 4Mbps.
The Linux/IrDA stack supports IrLAP, IrLMP, IrIAS, IrIAP, IrLPT, IrCOMM, IrOBEX, and IrLAN. Several of the protocols are implemented as both clients and servers. There is also support for multiple IrLAP connections, via several IrDA(TM) devices at once. The Linux/IrDA project started at the end of 1997 and its status is still experimental, so please don't expect every feature working straight. AFAIK Linux/IrDA is the _only_ open source IrDA implementation currently available.
Remote Control (RC) via infrared is the aim of the Linux Infrared Remote Control - LIRC project, and also described in this HOWTO.