Reading
this post recently let me to ask a question that has been puzzling me.
On the "My email addresses" screen in Settings, in the Type column some addresses have the word "Alias," but others do not. ALL the addresses are of the form <xxx@mydomain.com>, where mydomain.com has its nameservers pointed to FM.
What are these "other" addresses, and how in the world did I set them up?
What are the functional differences between "Alias" addresses and these "other" addresses?