About the author

Helder da Rocha has taught, written, and developed applications with Java and web technologies since 1995. In 1996, he wrote one of the first books in Portuguese about HTML and JavaScript. Since then he has created hundreds of presentations, tutorials, and course materials on Java, Java EE, programming tools, patterns, techniques, methodologies, HTML, CSS, JavaScript, SVG, XML, data visualization, Arduino, and the Internet of Things. He holds a master's degree in computer science. He also has a background in the visual arts and design and has some of his artwork in permanent museum exhibits. He lives in São Paulo, Brazil, where he works as an independent consultant, developer, and instructor, and is a frequent speaker at technological events.

I would like to thank my wife, Ana Carolina, and my daughter, Marina, for their patience and inspiration. Many examples created for this book use data from public portals and scientific publications. Thanks to the researchers for sharing it, which certainly made this book much more interesting. Finally, I must thank the creators of Chart.js 2.0, Ranner Linsley, Evert Timberg, and the GitHub community, since this book would not exist without them.