Some people are still confused about open source. Granted, the term is a bit over-used, but people are still referring to some educational products as open source. There’s a huge difference.
Open source hardware (OSHW) offers schematics, software, everything that is printable is free to use as you like. The Raspberry Pi (RPi) has a copyright notice on its schematics, so it is not true OSHW. However, the RPi is accessible via a low price. And it's popular with educators. But it's not near to being OSHW like Arduino, Launchpad, Beagleboard, and even the Intel Galileo & Edison products.
As far as I can discern, “open source” started with Linux in the user space, then migrated to embedded applications because it was royalty free and maintained by an army of altruistic engineers and computer scientists. (Even without a college degree, I would call anyone whose contributions are incorporated into a Linux tree as having earned the title.)
"Henrietta Lacks (1920-1951)" by [1]. Licensed under Fair use via Wikipedia.
Lynnette Reese holds a B.S.E.E from Louisiana State University in Baton Rouge. Lynnette has worked at Mouser Electronics, Texas Instruments, Freescale (now NXP), and Cypress Semiconductor. Lynnette has three kids and occasionally runs benign experiments on them. She is currently saving for the kids’ college and eventual therapy once they find out that cauliflower isn’t a rare albino broccoli (and other white lies.)