Sender's email address in Email Campaign

Hi Folks,

Whenever I am creating an email campaign in Communication Channel I enter Email as channel,I have to enter Sender or  email address .

So If I click on input help of Sender field it will take me to search screen of Employees "Search Employees".Does this mean Any employee can send an email outside sap?Or here we have to select the configured email address?Please help?

Regards

Jaya