This property contains the value that is transmitted in the From: header of the outgoing e-mail.
The value assigned to this property should be a valid e-mail address. It is considered to be bad practice to forge From addresses in mail headers, and some mail systems will not allow you to do this and will override the settings you define for this value.
Whatever value ends up in the From: header, the recipient can reply to this address if they mean to. It makes sense for this to be a mail address that a human being will ultimately check although you may want to put in some automation to read incoming e-mails if you expect a lot of responses.