In the past couple of weeks a quarrel has illustrated the value to advertisers of such fine-grained information: Should advertisers assume that people are happy to be tracked and sent behavioural ads?
Their value lies in cutting them up into snippets and relevant excerpts, and showing those snippets along with search ads to people looking for related information.
它们的价值在于，将它们划分为片断或相关摘录，再把这些片断和搜索广告一起展示给寻找相关信息的人们。
3
This may seem at odds with the value we place on relevant text-based ads.