1) Email worm 
ExploreZip, also known as I-Worm.ZippedFiles, is a destructive computer worm which attacks machines running Microsoft Windows. It was first discovered in Israel on June 6, 1999. Worm.ExploreZip is a worm that contains a malicious payload. The worm utilizes Microsoft Outlook, Outlook Express, or Exchange to mail itself out by replying to unread mes...