Firewire is a way of connecting devices together or to a computer.
FireWire is a name given by Apple to IEEE 1394, which is an interface standard for a serial bus for high-speed communications and real-time data transfer.
As a serial bus, FireWire transfers information one bit at a time. Developed in the 1980s and 1990s by Apple, the tech major intended FireWire to be a replacement for the parallel SCSI bus, while also providing connectivity for video and digital audio equipment.