Tomlinson was one of a group of scientists who were working on developing better computers. The scientists at his site were able to send a message to a “mailbox” on the computer on their site. Other scientists could view the messages in the mailbox. But there were other computers at other sites where scientists were working on the same project. Tomlinson’s is idea was to figure out a way to deliver messages to mailboxes on those remote computers. He used the @ sing to identify messages that were headed out of the local machine to the more distant ones. That was the start of the emailing systems that we still use to day.