From the introduction:
Google Chart Tools provide a perfect way to visualize data on your website. From simple line charts to complex hierarchical tree maps, the chart galley provides a large number of well-designed chart types. Populating your data is easy using the provided client- and server-side tools.
A chart depends on the following building blocks:
Chart Library
…
Data Styles
…
Data Sources
…
More tools for exploring data.
Not to mention making that analysis available to others.