Facebook has admitted, nearly two weeks after announcing that hackers had access to users' personal information, that 14 million users had their location data, search history, and a wide variety of other details stolen. The data includes check-in locations, previous searches, and a selection of other sensitive information, most of which you probably wouldn't want others to see. Unless you're some sort of weirdo or something, that is.
Facebook published a blog that stated "of the 50 million people whose access tokens we believed were affected, about 30 million actually had their tokens stolen.” Of the 30 million, Facebook split up those identified into specific groups: an initial sample group of 400,000, a second of 15 million, and third of 14 million, and the last round of 1 million, all of which had their information stolen in different waves.
The various groups each had different types of data usurped from the accounts. For instance, the 14 million users had a whole range of information stolen: username, gender, relationship status, religion, hometown, location, current city, birthdate, devices, education, work, check-ins and tags, website, followed people and Pages, and 15 recent searches. So basically everything. These people got it the worst, but let's face it, anyone affected got a serious wakeup call about how well Facebook is protecting and/or selling their data.
You can check and see if you were one of the Facebook users affected by going to this page from the social media platform itself and scroll down to see if you have a message stating as such. You should also have received a message about the hack and what you can do to potentially protect yourself from further issues in the future.