Many of us have had the same "pleasant surprise".After you mark a song as a favorite on a music app（程序），it suggests songs of the same kind to listen to （1） 　 　

   Big data（数据）is a lot of sets of information that are put together so they can be used by a computer program.It can have different kinds of information from many sources（来源），such as information that comes from schools，social media sites，companies，and governments. （2） 　 　Another set can have what they like，where they go to school，and how much time they spend on the computer.

   （3） 　 　The government uses it to understand how many people travel on buses or trains.The information is then used to make bus or train systems better.Companies use big data，too.It helps them understand who buys their products.For example，one company uses weather data to see when people eat the most ice﹣cream.

   Big data can be used for good reasons.Some hospitals use big data to predict if a baby who is born too early will get sick.The hospital can then take extra steps to take care of that baby so he or she does not get sick. （4） 　 　It can be used to predict which kinds of people are likely to break the law or hurt others，even if they have not done anything wrong.

   （5） 　 　It is because the computer programs used to look at big data and understand it are written by people.People think a certain way.Because they think a certain way，they build a model of those ideas.These ideas are then used to look at the data.Sometimes，these ideas are helpful for people or businesses.Other times，bad ideas can cause problems for certain groups of people.

A．	Big data can be used in many ways.
B．	Why do we use big data for bad things？
C．	Big data can also be used for bad reasons.
D．	How can big data be used for good and bad things？
E．	One set of data can have people's names and addresses.
F．	In fact，this magic，mind﹣reading power depends on data.