BitDefender has prepared this wonderful and a very informative Infographic on the history of computer viruses starting 1970. The history of malware is rife with incidents that allowed viruses to morph from innocent pranks to advanced military weapons.
The first Internet Worm and a great deal of MS-DOS viruses were harmless to both the user and the computer. They were designed to be annoying and let the world know about their creators existence.
But with the passage of times, things changed. Today’s malware writers exploit their creations to use infected machines, and then steal banking credentials, send spam messages, or leverage their revenue by advertisement click fraud. Corporate espionage also brings constant revenue, as malware opens backdoors into the organization’s network.
If you’d like to find out more about how malware grew in time, download this PDF copy of the Malware History whitepaper from BitDefender.
Which was the first Windows virus? Which was the first AntiVirus? may also interest you.

