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. That interaction can be more personal to users than traditional methods of outbound marketing and advertising. 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. 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. 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.
Webmasters and content providers began optimizing websites for search engines in the mid-1990s, as the first search engines were cataloging the early Web. Initially, all webmasters only needed to submit the address of a page, or URL, to the various engines which would send a "spider" to "crawl" that page, extract links to other pages from it, and return information found on the page to be indexed. The process involves a search engine spider downloading a page and storing it on the search engine's own server. A second program, known as an indexer, extracts information about the page, such as the words it contains, where they are located, and any weight for specific words, as well as all links the page contains. All of this information is then placed into a scheduler for crawling at a later date.