<p>I got accepted by my internship and they said this to me. As for your first day information, offer letter, drug screen and background information you will receive that by COB this week? When will I receive the document and is it going to be by mail?</p>
<p>COB is close of business, or the end of the work week. Other than that, there is no way for us to know how you will receive that document. If they have generally been emailing you, it is likely that you will get some of this info by email, but if many of those forms need signatures, they may send it by mail. This is really a question you should ask whoever is providing your internship.</p>