From finding a love match for free to helping you save the environment, new Facebook applications extend even further into a user’s life than ever before.

Applications are created by third parties that are not associated with Facebook, but who are allowed by Facebook to upload their inventions to its platform.

“Facebook’s Platform enables anyone, anywhere, to build complete applications that you can choose to use. The possibilities are endless. Define your experience on Facebook by choosing applications that are useful and relevant to your world,” Facebook’s Web site says.

Now the applications feature is more pervasive than ever because Facebook is allowing makers to include their applications on other Web sites.

In addition to the typical quizzes and friend-ranking applications, among the most popular, Facebook is steadily diversifying its applications functions.

Saving the Earth

“(Lil) Green Patch” and “Greenbook” together claim nearly a quarter-million users who attempt to combat global warming one square foot of rain forest or pound of carbon dioxide at a time. “The developers of ‘(Lil) Green Patch’ are using sponsorship revenue from advertisers to make donations to the Nature Conservancy’s Adopt an Acre program. Adopt an Acre is a program that provides critical funds for rainforest protection and restoration,” its Web site said. “Greenbook” uses a similar strategy, encouraging users to add the application in order to help buy back carbon dioxide emissions.

Learn something about yourself

Some applications delve deeply into your inner psyche. From finding the perfect bumper sticker that exemplifies your relationship with your best pals to learning which cartoon character is the imaginary version of you, the diverse and sometimes annoying assortment of applications can essentially tell you exactly who you are. “Which Beatles Song Describes Your Life Right Now?” allows you to express what you’re feeling through Beatles lyrics, while “IQ Test” explicitly tells you how smart you are.

Get connected

New applications are incorporating the features of online dating Web sites into the Facebook realm. Nearly 10 percent of the entire Facebook uses the application “Are You Interested?,” which presents users with random others’ profile pictures and allows you to decide whether or not you are interested. If you are lucky, you will learn who is interested in you as well. If not, you can still spend hours looking through profile pictures. “The Hookup” is a newly added application that follows in the footsteps of “Are You Interested?”

“Find new friendship, romance, bar crawlers, shopping friends, study buddies, and business partners with ‘The Hookup.’ Answer a few simple short questions to create a Hookup profile and start finding who you Hookup with the best!” its Web site says.