SEO stands for search engine optimization. SEO is the process of taking steps to help a website or piece of content rank higher on Google.
The key difference between SEO and PPC advertising (Pay-per-click) is that SEO involves “organic” ranking, which means you don’t pay to be in that space. To make it a bit simpler, search engine optimization means taking a piece of online content and optimizing it so search engines like Google show it towards the top of the page when someone searches for some keyword.
Search engine optimization is a key part of online marketing because search is one of the primary ways that users navigate the web.
Search results are presented in an ordered list, and the higher up on that list a site can get, the more traffic the site will tend to receive. For example, for a typical search query, the number one result will receive 40-60% of the total traffic for that query, with the number two and three results receiving significantly less traffic. Only 2-3% of searchers click beyond the first page of search results. Thus, even a small improvement in search engine rankings can result in a website receiving more traffic and potentially business.
Because of this, many businesses and website owners will try to manipulate the search results so that their site shows up higher on the search results page (SERP) than their competitors. This is where SEO comes in.
Search engines such as Google use an algorithm or set of rules to determine what pages to show for any given query and in which order. These algorithms have changed during time, evolved to be extremely complex, and take into account hundreds or even thousands of different ranking factors to determine the rankings of their SERPs. However, there are four core metrics that search engines evaluate to determine the quality of a site and how it should rank:
Links - Links from other websites play a key role in determining the ranking of a site in Google and other search engines. The reason being, a link can be seen as a vote of quality from other websites, since website owners are unlikely to link to other sites that are of poor quality. Sites that acquire links from many other sites gain authority (called "PageRank" in Google) in the eyes of search engines. Of course, not all links are equal, some are more worthy than others, some are even discarded, based on some metrics search engines use.
Content - In addition to looking at links, search engines also analyze the content of a webpage to determine if it would be relevant for any given search query. A large part of SEO is in creating content that is targeted towards the keywords that search engines' users are searching for. All content should be as unique as possible since search engines recognizes copies.
Page structure - The third core component of SEO is page structure. Because webpages are written in HTML, how the HTML code is structured can impact a search engine’s ability to evaluate a page. Including relevant keywords in the title, URL, and headers of the page and making sure that a site is crawlable are actions that site owners can take to improve the SEO of their site. Page usability is also factor, as bad mobile layout or text too small are seen as penalties.
The search engine optimization process involves optimizing each of four core components of search engine algorithms in order to rank higher in the search results.