What this ifconfig output telling me?
Tl;dr
For your Mac &quot;lo0&quot; is almost the same as the &quot;me&quot; is for you in your question!
lo0: is the loopback address of your computer:
wikipedia says:

Implementations of the Internet Protocol Suite include a virtual network interface through which network applications can communicate when executing on the same machine. It is implemented entirely within the operating system's networking software and passes no packets to any network interface controller. Any traffic that a computer program sends to a loopback IP address is simply and immediately passed back up the network software stack as if it had been received from another device.
Unix-like systems usually name this loopback interface lo or lo0.
Various Internet Engineering Task Force (IETF) standards reserve the IPv4 address block 127.0.0.0/8, in CIDR notation and the IPv6 address ::1 for this purpose. The most common IPv4 address used is 127.0.0.1. Commonly these loopback addresses are mapped to the hostnames, localhost or loopback.

en0:
en0 is your first physical network interface.
Usually it's the internal Ethernet nic (Network interface controller).
It's not activated - probably no ethernet cable is connected - and doesn't have an IP-address.
en1
en1 is your second physical network interface.
Usually it's the Wi-fi interface.
It's activated and connected to an access point and has the IP-address 192.168.1.2, the netmask 255.255.255.0 and the broadcast address 192.168.1.255.
fw0:
fw0 is your third physical network interface.
That's your Firewire interface.
It's not activated - probably no Firewire cable is connected - and doesn't have an IP-address.