For some websites, the approach is direct: they ask you to take a survey about what you like, and then make offers that match your interests.

有一些网站采用直接的办法：他们会对你的喜好进行调查，然后提供和你的兴趣匹配的服务。

Another way is through IP addresses, the electronic place from which you browse the Web.

另一种方法是通过IP地址，找到你经常浏览的网页地址。

The addresses provide websites with an easy way to target a particular person or household.

地址可以很轻易地提供信息，从中可以锁定一个特别的人或者一户人家。

Amazon.com and many other sites also compare individual's browsing and buying habits to those of thousand and millions of other consumers in their databases.

亚马逊网和许多其他网站也会比较个人和成千上万其他顾客的浏览和购买习惯，然后存入数据库。

Using a technique called collaborative filtering, they can find out your likely interests.

使用一种称作协同过滤的技术，他们能够找出你的可能兴趣。

This is based on what they know about what like-minded people buy or do.

这建立在他们知道那些想法一致的人会买什么，做什么。

A clothing store, for instance, would make a very different recommendation to a customer who is 39, married, intent on looking young and willing to spend US$500 than it will to a recent college graduate.

比如，一个服装店可能会对给一位39岁的已婚，想要看上去更年轻的顾客独特的建议，这位顾客的花费可能会比一个大学刚毕业的学生多500美元。

But this new use of Internet begins to trouble some computer users.

但是互联网的这种新颖的使用方法会对一些计算机用户带来一些麻烦。

They worry that advertisers can track you without your knowledge, and that files about them might be put to ill use somehow, or shared with wrong people.

他们担心广告商可能会在自己不知道的情况下被跟踪，一些和他们有关的文件会被一定程度上错误使用，或者和一些不应该分享的人分享。

Sometimes they just don't like being watched.

有时候他们只是不喜欢被关注。