Here is a list of 5 less known SEO factors and the effects on search engine rankings.
1. The location of the server
Google and other major search engines use the physical location of the server as a signal. This signal becomes even more important when the domains have a generic TLD (such .com, .net, .gov etc) and when their webmasters have not enabled the Geographic Targeting Feature on Google Webmaster tools console.
Nowadays search engines try to provide to the users not only trusted relevant pages but also the ones that are fresh. New pieces of content that are published by trusted websites are known to out-rank old pages that have lots of reputable links.
3. Social Media Reputation
Google and Bing confirmed that they use Social Media data in their algorithms. Since then several case studies have been published concerning the importance of Social Media in rankings. We should note that the social media popularity over time can be also used as a signal for page freshness.
4. Speed and Usability
Creating a good site with high quality content and offering a great user experience to the visitor is a solid strategy in order to improve your rankings and increase your organic traffic.
5. Web Performance Optimization (WPO)
Improves the user experience of your site by increasing server performance, reducing the download times. For WordPress users the W3 Total Cache plugin is a must have!