A very high speed serial interface, optimized for sustained data streams. Firewire is an Apple trademark for their implementation of the IEEE 1394 standard (which they developed), and all newer Macintosh computers starting with the G3 line include it as standard equipment. It is also appears in many Wintel platforms, and PCI-based Firewire add-on cards are widely available. In electronic music, Firewire has become the interface of choice for audio I/O involving multiple channels or higher sample rates; several companies have developed audio interfaces containing A/D converters with a Firewire ouput. In 2008, Apple created a controversy by introducing new Macbook models lacking a Firewire interface, which has created speculation on Firewire's future, as new USB standards are about to be introduced which will provide higher speeds for the competing interface standard.