Netstat question: Identifying local host

[Joel Hammer]

Abbreviated output from netstat -an looks like this:

tcp        0      0 0.0.0.0:515             0.0.0.0:*               LISTEN
tcp        0      0 192.168.1.11:53         0.0.0.0:*               LISTEN
tcp        0      0 127.0.0.1:53            0.0.0.0:*               LISTEN
udp        0      0 0.0.0.0:111             0.0.0.0:*
udp        0      0 192.168.1.11:123        0.0.0.0:*
udp        0      0 127.0.0.1:123           0.0.0.0:*

My question is, why is the local host sometimes identified
as 0.0.0.0, othertimes as 192.168.1.11 (its ip address),
and other times as 127.0.0.1?

Thanks,

Joel