Chapter 6. Creating Real-time Applications

	Nothing endures but change.
	--Heraclitus

What is real-time software? A list of friends gets updated the instant one joins or exits. Traffic updates automatically stream into the smartphones of drivers looking for the best route home. The sports page of an online newspaper immediately updates scoreboards and standings as points are scored in an actual game. Users of this type of software expect reactions to change to be communicated quickly, and this expectation demands a particular focus on reducing network latency from the software designer. Data I/O updates must occur along subsecond time frames.

Let's step back and consider the general characteristics of the Node environment and community that make it an excellent tool for creating these kinds of responsive network applications.

Some validation of Node's design, it may be argued, is found in the enormous community of open developers contributing enterprise-grade...