Keystone = Setting a retail price at twice the wholesale price.
Keyword = Main key phrase of a web page; words used by search engines to determine the content of a Web page.
Knowledgebase – a collection of facts, rules, and procedures that are organized into a searchable format. In Web 2.0, website knowledgebases are usually interactive.
KPI or Key Performance Indicator = Business metric that helps assess the present state of a business, by evaluating a set of factors that the business has identified as determinants to its success. KPI metrics help entrepreneurs understand the pulse of business.