Help support videos like this: http://www.cgpgrey.com/subbable
**CGPGrey T-Shirts for sale!**: http://goo.gl/1Wlnd
Grey’s blog: http://www.cgpgrey.com/blog/

Also check out MinutePhysics’ video: http://www.youtube.com/watch?v=53glKEPzElA & SciShow: http://www.youtube.com/watch?v=HnDsXhQHrEw