Link building is the process of attaining inbound links, or convincing sources on the Web to add hyperlinks on their websites that point to yours. Inbound links are a concern for businesses and marketers on the Web because they are one of the most important factors that impact search engine rankings, especially on Google. This gives inbound links the potential to significantly affect your business.
In order to understand the importance of link building, it's worthwhile to revisit why links are important on the Web in the first place.
A link is really just a path for visitors and search engines to get from one page to another on the Internet. Search engines use links to scan the Web and find relevant websites when people search. Links are also important within a single website, helping users and search engines easily navigate and find the information they need.
Google pioneered the use of backlinks as a major search engine ranking signal in the late 1990s, using them as a "vote" of popularity. Google's algorithm assigned different values to backlinks based on a link's location and the strength of the linking website.. Since then, Google and other search engines have created more sophisticated algorithms that evaluate even more aspects of link data, combining that information with many other metrics that ultimately determine how high a website ranks for a given term or phrase.
Despite the addition of other ranking signals, inbound links still have a major impact on rankings. What makes link building challenging is the way search engines grade the quality and relevance of links pointing to a website. Having more links than your competitors no longer guarantees that you will achieve higher rankings. In fact, links can now get your website penalized from Google.
In the spring of 2012, Google rolled out an algorithm update that drastically changed the future of search engine optimization. Dubbed "Penguin," the update aimed to prevent websites that used spammy or "black hat" link building tactics.
Webmasters who had previously loaded up their sites to improve their search engine standings - using tactics like buying links, dropping them in directories and blog comments, and trading them through link networks - suddenly saw their traffic plummet. Google started issuing manual or algorithmic penalties to websites with inbound links deemed "unnatural," resulting in a drastic drop in rankings or, in some cases, outright banishment from SERPs. Google updates Penguin several times per year, with plans to eventually release a version that updates in real time. Webmasters combat Penguin penalties by monitoring their internal and inbound links, removing what they can and disavowing (asking Google to ignore) the rest.
Google has introduced several adjustments to the Penguin algorithm update, continuing to refine the way it assesses links and the quality of websites based on that. As Penguin evolves and gets better at spotting unnatural links, it's more important than ever for webmasters to stay up-to-date with ill-advised tactics. Guest posting is one recent example of a marketing tactic that was highly effective for branding and building traffic; but when Google recognized that some marketers were using it exclusively for link building purposes, they cautioned against possible penalties.
As long as search engines use links to determine rankings, marketers will continue to find new ways of generating inbound links. The safest approach is to keep within the spirit of Google's guidelines. Focus on links as a conduit to audiences that will appreciate your content, rather than a signal for a search engine crawler. Instead of focusing exclusively on how to build links, channel some of those efforts into creating valuable content that webmasters and users worldwide genuinely want to share.