Websites such as Delicious, Digg, Slashdot, Diigo, Stumbleupon, and Reddit are popular social bookmarking sites used in social media promotion. Each of these sites is dedicated to the collection, curation, and organization of links to other websites that users deem to be of good quality. This process is "crowdsourced", allowing amateur social media network members to sort and prioritize links by relevance and general category. Due to the large user bases of these websites, any link from one of them to another, the smaller website may in a flash crowd, a sudden surge of interest in the target website. In addition to user-generated promotion, these sites also offer advertisements within individual user communities and categories. Because ads can be placed in designated communities with a very specific target audience and demographic, they have far greater potential for traffic generation than ads selected simply through cookie and browser history. Additionally, some of these websites have also implemented measures to make ads more relevant to users by allowing users to vote on which ones will be shown on pages they frequent. The ability to redirect large volumes of web traffic and target specific, relevant audiences makes social bookmarking sites a valuable asset for social media marketers.
Social networking websites are based on building virtual communities that allow consumers to express their needs, wants and values, online. Social media marketing then connects these consumers and audiences to businesses that share the same needs, wants, and values. Through social networking sites, companies can keep in touch with individual followers. This personal interaction can instill a feeling of loyalty into followers and potential customers. Also, by choosing whom to follow on these sites, products can reach a very narrow target audience. Social networking sites also include much information about what products and services prospective clients might be interested in. Through the use of new semantic analysis technologies, marketers can detect buying signals, such as content shared by people and questions posted online. An understanding of buying signals can help sales people target relevant prospects and marketers run micro-targeted campaigns.