Glossary

an alphabetical list of words relating to a specific subject, text, or dialect.

A key performance indicator (KPI) is a metric used for evaluating factors that are important to the success of an organization.

Described either as a number or a percentage, it represents the frequency at which a keyword or a phrase should appear in the content of a webpage, in comparison to the total number of words on that page.

Formula to calculate keyword density is 

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A keyword, with respect to search engine optimization, is a particular word or phrase that describes the content on your web pages.

Keywords are also used as a reference point for finding related words and information.