Firewire is IEE1394. Firewire is very fast (does not compare with 1
Gb/s Ethernet, however), at 100/200/400 Mb/s (IEEE1394b is 800 Mb/s, not
widely used yet but will be very soon). It has plug n play capability,
and can be plugged/unplugged without data loss. A lot of computers
come with Firewire (even if they don't have a plug). Most of the time
you can see two connections in your Network Connections even though you
have only one Ethernet device. One will be "Local Area Connection [x]"
(where x is just a number, it will not be there if you only have one),
the other will be "1394 Connection". The 1394 connection is the
Motherboard's Firewire connection from the Ethernet adapter to the
Ethernet is simply a networking standard. It too is plug n play. It
comes standard on all newer computers. Standard Cat5e cables are 100
mb/s. Most newer computers come equipped with a 1 Gb/s adapter, so
using 1 Gb/s connections are only a 1 Gb/s Hub/Switch/Router (or
crossover cable) away.
As for networking; Firewire (IEEE1394) CAN be used with networks. It
is used a LOT for networks. If you want to network with Firewire, get
an OEM card and a cable. You are now ready to network with Firewire.
Firewire is like USB, however it has more functionallity. It can
connect devices/peripherals and also network.