Recently Google has updated webmaster guideline, in webmaster guideline Google had written more specific information under Quality Guideline – specific guideline
Hidden Text or hidden links – information about hidden text and hidden links
Cloaking and Sneaky redirects – Information about Cloaking, Java Script Redirects and Doorway pages
Automated quires to Google
Load pages with irrelevant keywords – Information about Keyword Stuffing
Duplicated content – Information about Duplicate Content and how to protect your website from getting banned due to duplication
Pages created that install virus, Trojan, or other badware – Information about websites that spread virus and Trojan and how Google react on such websites
Unique content with helpful information that make users to stay on your website – Information about unique content that effect on website ranking.