History
Email has actually been around even before the Internet was in use. According to some accounts, MIT first developed Compatible Time-Sharing System (CTSS) in 1961. This allowed many users to log into an IBM 7094 from different dial-up terminals and store files online on a disk. This in turn encouraged users to share files and email started in 1965 for multiple people to communicate on a time-sharing mainframe computer. Email may have become network email, allowing users to communicate on different computers in 1966. In 1971, Ray Tomilson developed the @ sign to separate the user and the machine.