Proprietary software was invented in 1983, when the Apple vs Franklin lawsuit established a precedent extending copyright to cover binaries (previously "just a number"). The Free Software Foundation was established later that year as a conservative reactionary movement to roll back the clock, designing the GPL to turn the newly expanded copyright against itself.
Since then, proprietary software largely burnt itself out leaving decades of abandonware, and the FSF's importance receded until it overplayed its hand by splitting "the GPL" into multiple incompatible versions. Today the Linux kernel and Samba can't share code, even though they implement two ends of the same protocol, because they're under incompatible GPL versions. Adding GPL software to Android violates the trademark guidelines so you can't call the result Android, and the most popular license on github is "none specified".
As the guy who started the busybox lawsuits and an amateur computer historian, I'd like to talk about how we got here, what's the current state of open source licensing, and where might we wind up next. This is an updated version of the talk given at Ohio LinuxFest 2013.