Google publishes an API for charts: call the API with an URL and it serves a chart image. According to the published API, you can make the following types of charts:
I thought that was all I could do with the Google Charts API — I was wrong. According to a Google groups announcement, we can also make:
Google announced these additional chart types in October 2008 and hasn’t yet updated its published API. That’s too bad — these are great features. Here are some examples from Google.
Here’s a compilation of Google Chart API documentation sources posted to the Google group.