The Google Chart Tools: Image Charts module (Chart module for short) supports the creation of charts in a Drupal site, using Google Image Charts (GIC for short) as the charting library, for which no API key is required (though a live internet connection is needed to view the charts).

The Chart module is the most installed (popular?) native charting module, used by quite a lot of Drupal modules facilitating charting.

The chart_views sub-module of the chart module provides Views integration, to create charts using views.

Tip: if you're trying to get started with using the chart module, and trying to get a basic understanding of all the options and features that might be available, consider starting with this high level introduction of the various components that are available to construct a chart ... Especially the image there should help.

Documentation status

Please note that the creation of these community pages for the chart module is to be considered as a work-in-progress. For a summary of the current status about available documentation for the chart module, refer to these issues:

• #2369883: Create chart documentation.
• #2370851: Create community docu for chart.

While waiting for completion of these pages, please checkout any of these links:

• the Drupal Google Chart API wiki pages, which contains some (pretty old, and incomplete) documentation about the chart module. These wiki pages have been partially incorporated already in pages such as the Chart API Parameters (in which some undocumented features were documented already also ... e.g. that chart type 'map' is supported also).
• the Chart project home page.