A breadcrumb is a row of internal links at the top or bottom of the page that allows visitors to quickly navigate back to a previous section or the root page. Many breadcrumbs have the most general page (usually the root page) as the first, leftmost link and list the more specific sections out to the right. We recommend using breadcrumb structured data markup28 when showing breadcrumbs.
Expertise and authoritativeness of a site increases its quality. Be sure that content on your site is created or edited by people with expertise in the topic. For example, providing expert or experienced sources can help users understand articles’ expertise. Representing well-established consensus in pages on scientific topics is a good practice if such consensus exists.

Social networking websites allow individuals, businesses and other organizations to interact with one another and build relationships and communities online. When companies join these social channels, consumers can interact with them directly.[3] That interaction can be more personal to users than traditional methods of outbound marketing and advertising.[4] Social networking sites act as word of mouth or more precisely, e-word of mouth. The Internet's ability to reach billions across the globe has given online word of mouth a powerful voice and far reach. The ability to rapidly change buying patterns and product or service acquisition and activity to a growing number of consumers is defined as an influence network.[5] Social networking sites and blogs allow followers to "retweet" or "repost" comments made by others about a product being promoted, which occurs quite frequently on some social media sites.[6] By repeating the message, the user's connections are able to see the message, therefore reaching more people. Because the information about the product is being put out there and is getting repeated, more traffic is brought to the product/company.[4]

In 1998, two graduate students at Stanford University, Larry Page and Sergey Brin, developed "Backrub", a search engine that relied on a mathematical algorithm to rate the prominence of web pages. The number calculated by the algorithm, PageRank, is a function of the quantity and strength of inbound links.[22] PageRank estimates the likelihood that a given page will be reached by a web user who randomly surfs the web, and follows links from one page to another. In effect, this means that some links are stronger than others, as a higher PageRank page is more likely to be reached by the random web surfer.
Optimizing a website may involve editing its content, adding content, modifying HTML, and associated coding to both increase its relevance to specific keywords and to remove barriers to the indexing activities of search engines.[citation needed] Promoting a site to increase the number of backlinks, or inbound links, is another SEO tactic. By May 2015, mobile search had surpassed desktop search.[3]