What does syncing email do?

A

AC Question

I need a good explanation of how my android phone "syncs" email. If the email is downloaded to the phone, is it then deleted from the server? If the email is deleted on the phone, is it deleted from the server?

And what about the sync schedule? If I set it to "manual", when does it update? Seems like with it set to "manual", emails still accumulate on the phone even though I haven't consciously done anything to download them.

Then there's the "period to sync email"...I am assuming that if I set it to the default 3 days, then sync ignores messages more than three days ago.

Ideally I would like to only download email to the phone when I cons andciously request it, and for the phone to never cause anything to be automatically deleted from the server.