Link-based analysis is an extremely useful way of measuring a site’s value, and has greatly improved the quality of web search. Both the quantity and, more importantly, the quality of links count towards this rating.
However, some SEOs and website owners engage in the practice of buying and selling links that pass PageRank, disregarding the quality of the links, the sources, and the long-term impact it will have on their sites.
Buying or selling links that pass PageRank violates our webmaster guidelines. Such links can hurt relevance by causing:
交易連結會導致以下傷害搜尋關聯性的問題——
Inaccuracies: False popularity and links that are not fundamentally based on merit, relevance, or authority
Inequities: Unfair advantage in our organic search results to websites with the biggest pocketbooks
Not all paid links violate our guidelines. Buying and selling links is a normal part of the economy of the web when done for advertising purposes, and not for manipulation of search results.