Facebook Questions beta lets you pose questions to Facebook community to get a broader set of answers and learn valuable information from over 500 million users. To ask publically, just click "Ask Question" button at the top of homepage. And for personal, ask a question to your friends or specific group, you can pose it as a status update on your profile targeted to those people. You can also add a photo or a poll to a question.
To show your question to most relevant people for ensuring best answers, you can tag it with a specific topic. Tagging themes also helps others benefit from the knowledge of everyone on Facebook.
You can browse answers from people with deep knowledge on a topic or click "Follow" under any question to receive a notification each time someone submits a new answer. And to browse through all, just select "Everything" from "Questions about" drop-down menu at top of the app, and click "Next Question" to start exploring questions and sharing your answers.