When would this be useful? If your site has a blog with public commenting turned on, links within those comments could pass your reputation to pages that you may not be comfortable vouching for. Blog comment areas on pages are highly susceptible to comment spam. Nofollowing these user-added links ensures that you're not giving your page's hard-earned reputation to a spammy site.
Engagement with the social web means that customers and stakeholders are active participants rather than passive viewers. An example of these are consumer advocacy groups and groups that criticize companies (e.g., lobby groups or advocacy organizations). Social media use in a business or political context allows all consumers/citizens to express and share an opinion about a company's products, services, business practices, or a government's actions. Each participating customer, non-customer, or citizen who is participating online via social media becomes a part of the marketing department (or a challenge to the marketing effort). Whereas as other customers read their positive or negative comments or reviews. Getting consumers, potential consumers or citizens to be engaged online is fundamental to successful social media marketing. With the advent of social media marketing, it has become increasingly important to gain customer interest in products and services. This can eventually be translated into buying behavior, or voting and donating behavior in a political context. New online marketing concepts of engagement and loyalty have emerged which aim to build customer participation and brand reputation.
Blogging website Tumblr first launched ad products on May 29, 2012. Rather than relying on simple banner ads, Tumblr requires advertisers to create a Tumblr blog so the content of those blogs can be featured on the site. In one year, four native ad formats were created on web and mobile, and had more than 100 brands advertising on Tumblr with 500 cumulative sponsored posts.
Popular social media such as Facebook, Twitter, LinkedIn, and other social networks can provide marketers with a hard number of how large their audience is nevertheless a large audience may not always translate into a large sales volumes. Therefore, an effective SMM cannot be measured by a large audience but rather by vigorous audience activity such as social shares, re-tweets etc.
Apple's iPhone 5c: Created a Tumblr page, labeling it "Every color has a story" with the website name: "ISee5c". As soon as you visit the website, the page is covered with different colors representing the iPhone 5c phone colors and case colors. When you click on one of the colored section, a 15-second video plays a song and "showcases the dots featured on the rear of the iPhone 5c official cases and on the iOS 7 dynamic wallpapers...", concluding with words that are related to the video's theme.
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. https://libertymarketing.tumblr.com/