Social media can be used not only as public relations and direct marketing tools but also as communication channels targeting very specific audiences with social media influencers and social media personalities and as effective customer engagement tools. Technologies predating social media, such as broadcast TV and newspapers can also provide advertisers with a fairly targeted audience, given that an ad placed during a sports game broadcast or in the sports section of a newspaper is likely to be read by sports fans. However, social media websites can target niche markets even more precisely. Using digital tools such as Google Adsense, advertisers can target their ads to very specific demographics, such as people who are interested in social entrepreneurship, political activism associated with a particular political party, or video gaming. Google Adsense does this by looking for keywords in social media user's online posts and comments. It would be hard for a TV station or paper-based newspaper to provide ads that are this targeted (though not impossible, as can be seen with "special issue" sections on niche issues, which newspapers can use to sell targeted ads).
Social networking sites such as Facebook, Instagram, Twitter, MySpace etc. have all influenced the buzz of word of mouth marketing. In 1999, Misner said that word-of mouth marketing is, "the world's most effective, yet least understood marketing strategy" (Trusov, Bucklin, & Pauwels, 2009, p. 3). Through the influence of opinion leaders, the increased online "buzz" of "word-of-mouth" marketing that a product, service or companies are experiencing is due to the rise in use of social media and smartphones. Businesses and marketers have noticed that, "a persons behaviour is influenced by many small groups" (Kotler, Burton, Deans, Brown, & Armstrong, 2013, p. 189). These small groups rotate around social networking accounts that are run by influential people (opinion leaders or "thought leaders") who have followers of groups. The types of groups (followers) are called: reference groups (people who know each other either face-to-face or have an indirect influence on a persons attitude or behaviour); membership groups (a person has a direct influence on a person's attitude or behaviour); and aspirational groups (groups which an individual wishes to belong to). https://www.facebook.com/Liberty-Marketing-3011004768971837/