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Facebook CEO Mark Zuckerberg.
- Data breaches in 2018 compromised the personal information of millions of people around the world.
- Here are 21 of the biggest data breaches that companies faced this year.
It seems like every week, a new company has to notify its customers that their data may have been compromised, and personal information may have been affected.
Data breaches can happen for a variety of reasons. Some companies are hacked. Data can be mishandled or sold to third parties. Holes in a website's security system can leave information unprotected.
One of the latest victims was Marriott hotels, which recently revealed that hackers had accessed the information of an estimated 500 million customers.
Some of the biggest victims in 2018 include T-Mobile, Quora, Google, and Orbitz. Facebook dealt with a slew of major breaches and incidents that affected more than 100 million users of the popular social network.
Here are the biggest data breaches that were revealed this year, ranked by number of users affected: