Unless you've lived in a cave with no connectivity for the last few years, you've heard about Angry Birds. Angry Birds Free is the introduction to the series and acts as a teaser for the paid app. Angry Birds Free downloads and installs with no problem.
The goal of Angry Birds Free is to launch birds from a slingshot, aiming them at structures with green pigs scattered about. The birds, some of which have special capabilities, knock over the building structures and kill the pigs. Wipe out the pigs and you pass the level. Sounds simple (and to many it sounds mindless!), but as millions will attest, there's an addictive quality to Angry Birds that keeps most players coming back and purchasing the expansion packs (there's a few out now). Angry Birds Free includes 24 levels that are not in the full game, so this isn't a sampler of the bigger pack but a stand-alone game by itself.
Angry Birds Free is the introductory app to a retail and gaming phenomena, and one you really should try just so you know what the fuss is about. Whether you get hooked or not is up to you, but there's a lot of fun to be had in Angry Birds Free.