This is student manual of the 4th mini-course in the computer literacy series. It discusses tha various types of E-Mail boxes and their function. It explains E-Mail addresses. It illustrates what happens when an E-Mail is sent and received It discusses the use of attachments. It teaches what happens when an E-Mail is deleted, forwarded, replyed to, moved or copied. This tool is a standard tool in the business world and should be understood.