Users can freely add hyperlinks to each of those locations, and due to their length, it isn't always clearly sensible to mild each single one of those links. So, so one can deter link spammers from taking advantage of a website's PageRank, the website online will regularly pick out to use the nofollow characteristic to all hyperlinks posted by means of different users.
Another use for the nofollow attribute is for advertisers to apply on links which have been paid for. So, if you buy an advertising banner on a internet site which hyperlinks to you, Google says that the nofollow attribute have to be introduced in order that they know no longer to bypass any PageRank across that link. The idea here is which you shouldn't advantage within the natural effects via buying advertisements that consist of links on other web sites.
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