Tomorrow is a special day for spam—it’s turning 30. Even those despised emails about enlarging certain body parts, discounts on health products, Rolex watches, enhancing your love life have to have an origin.

In fact, spam began inoffensively enough with an email sent May 3, 1978 to about 400 users of Arpanet, (the government-run network that later became in the Internet) from a marketer at the (now defunct) computer company Digital Equipment Company. The first one wasn’t the scam- and virus-filled message familiar to today’s Internet users—just a friendly email inviting all to a showing of a new computer system.