Search engine optimization (SEO) is the process of affecting the visibility of a website or webpage in a search engine’s unpaid results (often referred to as natural, organic, or earned results). Typically, the earlier or higher ranked on the search results page, and more frequently a site appears in the search results list, the more visitors it will receive from the search engine’s users. SEO may target different kinds of search, including image search, local search, video search, academic search, news search, and industry-specific vertical search engines.
Google’s Matt Cutts
On-Site and Off-site SEO
On-Site SEO are rules you can apply on your website or blog so that it’s more search engine friendly. For example, using proper titles, good descriptions, well-formatted URLs, correct use of H1, H2, tagging images, etc.
Off-site SEO refers to the process of getting votes from other websites for the purpose of increasing your web site’s trust in the eyes of search engines. Votes in our case are links coming from other websites to your site. That is also the reason why off-site SEO is referring to as link building. It’s not only a matter of how many links you have pointing to your website, but also from where these links are coming from.
Google’s Matt Cutts
SEO techniques can be classified into two broad categories: techniques that search engines recommend as part of good design, and those techniques of which search engines do not approve. Industry commentators have classified these methods, and the practitioners who employ them, as either white hat SEO, or black hat SEO. White Hat SEO tends to produce results that last a long time, whereas black hats anticipate that their sites may eventually be banned either temporarily or permanently once the search engines discover what they are doing.
White hat SEO is not just about following guidelines but is about ensuring that the content a search engine indexes and subsequently ranks is the same content a user will see. White hat advice is generally summed up as creating content for users, not for search engines, and then making that content easily accessible to the spiders, rather than attempting to trick the algorithm from its intended purpose. White hat SEO is in many ways similar to web development that promotes accessibility.
Black hat SEO attempts to improve rankings in ways that are disapproved of by the search engines, or involve deception. One black hat technique uses text that is hidden, either as text colored similar to the background or positioned off screen. Another method gives a different page depending on whether the page is being requested by a human visitor or a search engine, a technique known as cloaking.
The leading search engines, such as Google, Bing and Yahoo!, use crawlers to find pages for their algorithmic search results. Pages that are linked from other search engine indexed pages do not need to be submitted because they are found automatically. Two major directories, the Yahoo Directory, and DMOZ both require manual submission and human editorial review. Google offers Google Webmaster Tools, for which an XML Sitemap feed can be created and submitted for free to ensure that all pages are found, especially pages that are not discoverable by automatically following links. Search engine crawlers look at a number of different factors when crawling a site.
A variety of methods can increase the prominence of a webpage within the search results. Cross linking between pages of the same website to provide more links to important pages may improve its visibility. Updating content so as to keep search engines crawling back frequently can give additional weight to a site. Adding relevant keywords to a web page’s meta data, including the title tag and meta description, will tend to improve the relevancy of a site’s search listings, thus increasing traffic. URL normalization of web pages accessible via multiple urls, using the canonical link element via 301 redirects can help make sure links to different versions of the url all count towards the page’s link popularity score.
- Organic search drives the most traffic of all channels, and is responsible for nearly half (47%) of all visits, compared to paid search, which drives only 6% of all visits.(Conductor, 310 Million Visits: Nearly Half of All Web Site Traffic Comes From Natural Search, Jun 2013)
- Nearly 4 out of 5 B2B buyers start their product research online at a search engine. Of those, 6% use Google.(Salesforce, The State of Demand Generation, Nov 2013)
- When it comes to Customer Lifetime Value, the highest-value customers arrive through organic search (54% higher than average-value customers).(Custora, E-Commerce Customer Acquisition Snapshot, Jun 2013)
- Leads gained through organic search have a 6% rate of close, while leads gained through outbound marketing efforts have a closing rate of only 1.7%.(Top Rank Marketing, War of Words, Jan 2013)
- Best-in-class companies are more than twice as likely as other companies to have a process to review website content for SEO (68% vs 28%).(Aberdeen Group, Benchmark: Web Experience Management from Content to Customer, Jun 2012)
- For ecommerce, organic search is #1 for acquiring new customers, accounting for nearly 16% of first-time-customer purchases. Social channels lag far behind, with Facebook and Twitter accounting for less than 0.25% of new customer acquisitions.(Custora, E-Commerce Customer Acquisition Snapshot, Jun 2013)
- Sites listed on the first Google search results page generate 5% of all traffic from an average search. Additionally, achieving the #1 spot for a given keyword means getting about 33% of the clicks.(Chitika Insights, The Value of Google Result Positioning, Jun 2013)
- For URLs that rank in the Top 10 of Google search results, the average user time on site is 101 seconds, and the average bounce rate is 37%.(Searchmetrics, SEO Ranking Factors and Rank Correlations 2014, Sep 2014)
- The average length of of a Top 10 URL on Google search results is 36 characters.(Searchmetrics,SEO Ranking Factors and Rank Correlations 2014, Sep 2014)
- 70% of search traffic comes from long-tail search terms.(SEOMoz,Beginner’s Guide to SEO, Oct 2014)