Search Engine Optimization (SEO) is the buzz thing nowadays in the internet and for a good reason. SEO service is an attempt to optimize sites to make them appear on a high position in the organic result page of Google. To achieve that, it has to fit a website to Google’s rules and their algorithms. No one know the exact algorithmic factors of it but decades of SEO experiences has resulted the community to have a pretty good idea about the important factors.
The factors can be divided in 2 categories, on-page factors and off-page factors. On-page factors include technical issues and textual issues on your sites. E.g How fast does your site load? Does your site contain the relevant wordings with the search queries. Off-page factors include mainly on activities done off the site, mainly Link building. E.g How many other authority and relevant sites link to you?
This infographics below provide a clear and simple explanation on the in and out in the world of SEO.
Infographic URL: http://digitrio.com.sg/what-is-seo/