Before we get to the faucets, Bitcoin is a virtual crypto currency—I penned a Bitcoin primer a while back if you're looking for more information. Bitcoin faucets aren't going to make you rich, but these are faucets I can personally attest pay out when and how they say they will as I've collected 0.34 BTC from them.

The first Bitcoin faucets were designed as promotional vehicles to get people interested and involved in Bitcoins back when a Bitcoin was worth a few pennies. A few people who had tons of Bitcoins that weren't worth much at the time thought that if they got them into the hands of more people, it would generate interest.

Today's so-called faucets are much more of a business model. Most of them work by paying out tiny fractions of a Bitcoin in exchange for loading a page full of ads or for watching videos. I also have one site to show you that's not a faucet, per se, but rather a site that pays Bitcoins in exchange for doing crowd-sourced tasks.
http://www.macobserver.com/tmo/article/get-free-bitcoins-with-8-website-faucets-that-really-pay