In 2007, Google announced a campaign against paid links that transfer PageRank.[30] On June 15, 2009, Google disclosed that they had taken measures to mitigate the effects of PageRank sculpting by use of the nofollow attribute on links. Matt Cutts, a well-known software engineer at Google, announced that Google Bot would no longer treat any nofollow links, in the same way, to prevent SEO service providers from using nofollow for PageRank sculpting.[31] As a result of this change the usage of nofollow led to evaporation of PageRank. In order to avoid the above, SEO engineers developed alternative techniques that replace nofollowed tags with obfuscated JavaScript and thus permit PageRank sculpting. Additionally several solutions have been suggested that include the usage of iframes, Flash and JavaScript.[32]

Social media marketing involves the use of social networks, consumer's online brand-related activities (COBRA) and electronic word of mouth (eWOM)[75][76] to successfully advertise online. Social networks such as Facebook and Twitter provide advertisers with information about the likes and dislikes of their consumers.[61] This technique is crucial, as it provides the businesses with a "target audience".[61] With social networks, information relevant to the user's likes is available to businesses; who then advertise accordingly. Activities such as uploading a picture of your "new Converse sneakers to Facebook[75]" is an example of a COBRA.[75][76] Electronic recommendations and appraisals are a convenient manner to have a product promoted via "consumer-to-consumer interactions.[75] An example of eWOM would be an online hotel review;[77] the hotel company can have two possible outcomes based on their service. A good service would result in a positive review which gets the hotel free advertising via social media. However, a poor service will result in a negative consumer review which can potentially harm the company's reputation[78].
Social media itself is a catch-all term for sites that may provide radically different social actions. For instance, Twitter is a social site designed to let people share short messages or “updates” with others. Facebook, in contrast is a full-blown social networking site that allows for sharing updates, photos, joining events and a variety of other activities.