FireWire 

High speed serial interface defined by Apple Computer in 1994. FireWire is a trademark; the interface may be referred to as IEE1394 withut paying royalties to Apple. FireWire allows the attachment of up to 63 devices to a single controller and allows for hub or daisy-chain topolgies. It was designed as a next-generation replacement for SCSI and is used to connect cameras, AV equipment, hard drives and optical drives to computer equipment.
FireWire can operat at 100,200,400 and 800 Megabits per second and there are 4, 6 and 8 pin variants on the physical connectors.
Sony have their own branding for FireWire - they refer to it as i.Link

The iMac has two FireWire ports on the back.

FireWire by Shalroth May 23, 2005

FireWire 

Failure of a Personal Computer interface designed to attach peripherals needing high bandwidth. Never achieved wide adoption and currently only supported by Apple fan-boys.

Hey look at my new Power iFail Pro 20x-t6......it has 6 FireWire ports.

FireWire by C0vetous April 16, 2009

Firewire 

Fire wire isnt really wire, but it has to do with wire. Firewire is when you take a piece of steel wool and tie a piece of wire around it, then you light the steel wool and swing it around which send massive ammounts of sparks flying everywhere.

"Hey Jimmy, wanna go make some firewire? Sure!"

Firewire by D-a-n November 28, 2007

FireWire 

Someone who is only slightly insane.

That guy is SO FireWire

FireWire by FW280 February 24, 2004

Angry Firewire 

Ginger Pubic Hair

Man, that Red-head has an amazing figure but I don't think I'll ask her out, Angry Firewire really puts me off muff-diving....

Angry Firewire by Xalior September 28, 2009