mac mail general questions

[saladiro]

Hi, have some general questions about mac mail preferences

1) what does it mean to have the box checked "store sent messages on the server"? aren't they already in my mac mail sent box?

2) similar to the above for drafts, jun, and trash, how come there is no option for "store received messages on the inbox"

3) when replying to a message, is there a way for the cursor to not be right on top of the below message I am responding to? Perhaps have it so it looks like I hit the enter button once or twice....

tks!