While your personal computer only keeps one copy of a file, large-scale services like Facebook rely on what are called content delivery networks to manage data and distribution.

虽然你的个人电脑只能保存一个文件的一个副本，但像 Facebook 这样的大型服务项目，则会依赖于所谓的内容分发网络来管理数据和分发。

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In this example we maintain only one copy of the data.

在这个例子中，我们仅维护数据的一个副本。

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Remember that any copy you make only contains the data that was in the individual files at the point in time the copy was made.

请记住，您所建立的任何副本仅包含在进行复制操作时对应的文件中所包含的数据。

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This makes sense given that the guidelines in current form are meant to apply only to data on information technology systems rather than hard-copy storage, with portal providers receiving and making use of some of the heaviest volume of customer data in China.

FORBES: China: Seeking Balance In Regulating Data Privacy