Facebook was once exclusive to Harvard.
Why it is true
It was called 'TheFacebook' and access was restricted to university students, expanding to the general public only years later.
Source: Social Media History
Would you rather be asked first?
This is the reading side of the site, so the answer is in the sentence above — that is the whole point of it. Test yourself works the other way round: the question comes on its own, and the fact and the explanation only appear once you have answered.