How to transfer files between computers on a network

[Josef Lowder]

Well, I think I'm finally getting closer, now that I understand
what the actual syntax should look like with real data in it.
This is what I tried:

$ scp /home/joe/mydata/track2 joe at 192.168.1.66:/home/joe/mydata/track2

That seemed to almost work ... except I got this reply:

ssh: connect to host 192.168.1.66 port 22: Connection refused
lost connection

So why would that connection be refused, and how do I fix that?