Email is more and more in the news these days, is near the center of the current US Attorney firing scandal, and for good reason. A substantial amount of communication flows via email, which can be an efficient form of communicating memos and other intercourse. Email is nearly instantaneous, costs almost nothing, and has in large part replaced the paper memo. Email provides for a path of inquiry that previously was unavailable to investigators for a paper document can be shredded or burned while email leaves a trail even when deleted. Furthermore, unlike a piece of paper, the email itself reveals who sent it and who received it, when and where. As Senator Patrick Leahy says (quoted by Michael Abramowitz on April 14, 2007 in 4 years of Rove e-mails are missing, GOP admits) "You can't erase e-mails, not today...They've gone through too many servers. Those e-mails are there -" There are primarily three kinds of email in common use. One is the email client program, a genre that includes Microsoft Outlook Express, Mozilla Thunderbird, Macintosh Mail, and Netscape Mail. The second type is the prevalent Microsoft Outlook, a very different program from the same company's Outlook Express. The third is commonly known as web mail or Internet mail.