Many people used to make a lot of money by designing pages purely for Adsense,
with no content but repetitions of keywords within text to which any keyword could be added.
They literally made thousands of dollars daily until Google caught on and applied duplicate content penalties and also contextual analysis of web page content, that they termed LSI (Latent Semantic Indexing).
Although designed with well positioned Adsense, these websites are constructed to achieve high listings in search engines and earn a lot of money from each of a few websites rather than a little money from each of many.
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