The primary goal of the spammers is to increase the search engine ranking for their client sites, in a process called "black hat search engine optimization (SEO)" or "Spamdexing".

垃圾信息散布者的主要目的就是提高其客户站点在搜索引擎的排名，这个过程被称为 “黑帽式搜索引擎优化（SEO）” 或 “垃圾索引”。

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Yes, Matt and his team are diligent in penalizing black hat sites, but they are very helpful in giving tips to the innocent owners who are trying to do right by Google.

FORBES: One CEO's Experience: Yes, You Can Accidentally Hire a Black Hat SEO