The
Linux kernel part and
device driver that handles handling of various
video capture devices, including
TV tuner cards and other similiar devices (such as some
digital cameras).
Linux video capture interface: v1.00
bttv0: Brooktree Bt848 (rev 18) bus: 0, devfn: 80, irq: 9, memory: 0xea010000.
bttv: 1 Bt8xx card(s) found.
bttv0: NO fader chip: TEA6300
bttv0: model: BT848(Miro)
It started out as a driver (bttv) for Brooktree BT848 card that is among the most common chipsets found in TV cards.
Note that this driver doesn't actually handle monitors, just devices that input video - the X11 server, frame buffer driver and the forever-if-ever-upcoming GGI do the output.
The video4linux API is good for basic stuff, but is somewhat limited. There's a new video API in works, called (not surprisingly) V4L2.