if i have a computer ,the computer have three network cards,install the suse os .
in the beginning, the system named the three network cards eth0 eth1 eth2 . i want to know it define what rules ?

for example three network A B C
A eth0
B eth1
C eth2

why network card A name eth0,not network card B name eth0.


i know it can be change by myself, but i want to know the default rules...
i am poor in english ,i don't know whether i say clearly .

if you have some suggestion ,please tell me
my e_mail:jaosn.guangye@gmail.com