Spam– unsolicited messages that fill our email inboxes to the brim– are a common sight nowadays, but it wasn’t until this date in 1978 that the first email spam was sent. The message was composed by Gary Thuerk, a Digital Equipment Corporation marketer who was promoting presentations of the DECSYSTEM-20 computer. The message was sent to hundreds of users on ARPANET, majority of whom immediately reacted negatively to the message. One user even claimed that the message shut down his system. Due to the almost universally negative reaction, it was a long time before spam started invading inboxes again.