First released in February, 2012, it's makers say they will soon sell their one millionth unit.
Thanks to its low cost (there's also a $25 version), the tiny computer has become very popular with hobbyists, or "makers," who prefer to create their own
It turns out, you can do a lot with a very basic PC. Each Pi includes an ARM-based CPU; a graphics processor; and a few ports and pins to connect it to other electronics.