Google Chart Tools
Google used to have two different charting platforms. One created static JPG images, but that is being phased out. What's left is the chart tools API for making interactive charts to embed on a website.
Interestingly, Google's chart tools include what Google calls a "Chart tools data source" protocol. That lets you do SQL-like queries on your data, and that protocol is implemented by Google Spreadsheets and Fusion Tables.
However, keep in mind that Google cleans house and kills off services from time to time -- something to consider when choosing to rely on Google APIs for long-life projects.
Find it at: https://developers.google.com/chart/