Lowell Heddings, better known online as the How-To Geek, spends all his free time bringing you fresh geekery on a daily basis. You can follow him on Google+ if you'd like.
DID YOU KNOW?
The SPF, or Sun Protection Factor, of sunscreen is representative of the amount of UV radiation the sunscreen blocks; a sunscreen with an SPF rating of 30 will allow 1/30th of the UV radiation to reach the skin (blocking 29/30ths, when applied properly, from reaching the skin). Conventional sunscreens are designed to block UVB radiation while broad-spectrum sunscreens are designed to protect against both UVB and UVA radiation.