A heat map is a picture of a web page that shows where users click when they visit a particular page.

The areas that are clicked most often appear in red (hot spot), while the areas clicked least often appear in blue or with no colour at all.

Heat maps are a tool used by web developers as part of their website usability testing routines.

Understanding how your visitors behave when they visit your web site is crucial to improving its effectiveness.

A variant on the heat map of mouse click is an eye tracking heat map which gives an inidcation of what catches most peoples' eye when they visit pages on your website.

You will require special third party software or an third party service if you wish to create a heat map of pages on your web site as they are currently not a standard part of analysis and statistics packages for tracking web sites.