jargon.artrocity.com
New Hacker's Dictionary the Jargon File v 4.4.6
[play on ‘copyright’ and ‘copyleft’]
1. The copyright notice carried by the various flavors of freeware BSD. According to Kirk McKusick at BSDCon 1999: “The way it was characterized politically, you had copyright, which is what the big companies use to lock everything up; you had copyleft, which is free software's way of making sure they can't lock it up; and then Berkeley had what we called ‘copycenter’, which is ‘take it down to the copy center and make as many copies as you want’”.