What if we want to include data visualization as an integral part of the site, not just an isolated figure or an interactive chart? When we’re designing interfaces for browsing data-driven sites, it’s valuable to be able to create navigation elements that are also visualization tools. We can keep the user informed as they explore, so they can make better decisions about what they’re looking at and what they’re clicking on.

What we need is something in between—markup that’s appropriate for navigation, but with some extra hooks for semantics and structure.

A List Apart has published an article of “Accessible Data Visualization with Web Standards“, shared three basic techniques for incorporating some simple data visualization into standards-based navigation patterns. All of them start with the building block of HTML navigation: an unordered list of links.

You should also look at Sparkline PHP Graphing Library. It provides a wide range of options how your graphs are rendered. It’s important that sparklines are visually appealing, especially in the restricted visual environment of the web. Web sparklines should approach as closely as possible the aesthetic of printed sparklines. Sparkline is completely free to use on your personal website, company home page, or to include in your commercial product. Sparkline is distributed under the BSD license.

A List Apart Article: Accessible Data Visualization with Web Standards
A List Apart Demo: http://alistapart.com/d/accessibledata/example-final.html
Sparkline PHP Graphing Library: http://sparkline.org/
License: BSD License