STEVE: And that’ll also be the IP that their router participates in the Local Area Network from. Now, the subnet mask of that can vary. But, for example, it’s often 255.255.255.0. Or it might be 255.255.0.0. But either way, the idea is that the IP that a packet is destined for, that is, the target IP, is compared against this subnet mask to see if the digits where we’ve got 255s are the same as the machine’s own IP, essentially. The idea being, for example, that a computer connected in the LAN might be 192.168.0.2, for example. If it’s sending a packet to any IP with the last byte different, so like .2, .3, .4, where the left-hand side of the IP has all the same numbers, 192.168.0, well, it knows that, because of the subnet mask, which is saying, essentially, specifying which IPs are in the local network, it’s saying, okay, you know, this machine is directly reachable by me. So it addresses the packet to that machine that it’s sending the data to directly, as opposed to saying, for example, if you were connecting to Microsoft, and you had some completely different IP, you know, 4.79.something else, it would notice that the digits were different where the subnet mask was a 255.255. That’s sort of the whole key to this. That tells it that this is an IP not on the Local Area Network, but one that is located somewhere else.