An interactive software application developed to utilize the core technologies of the Facebook platform to create an extensive social media framework for the app.
While it hasn't been possible to exchange real currency directly within Facebook Apps and Facebook Games, apps can utilize Facebook's Facebook Credits, a virtual currency that can be purchased (with actual money) in order to acquire virtual goods and services within Facebook apps and games.
Facebook is undeniably one of the best places to keep in touch with friends, and one of the reasons it's so popular are its applications. Most of Facebook's user-favorite features, like its massively popular photo sharing, video sharing, user groups, or events functionality, are powered by applications. These core apps come installed by default on every user's profile and cannot be removed.