Reactive Programming is both an overloaded term and a broad topic. As such, this book will focus on a specific formulation of Reactive Programming called Compositional Event Systems (CES).
Before covering some history and background behind Reactive Programming and CES, I would like to open with a working and hopefully compelling example: an animation in which we draw a sine wave onto a web page.
The sine wave is simply the graph representation of the sine function. It is a smooth, repetitive oscillation, and at the end of our animation it will look like the following screenshot:
This example will highlight how ...