4

Variables

All of the books in the world contain no more information than is broadcast as video in a single large American city in a single year. Not all bits have equal value.

—Carl Sagan

Believing oneself to be perfect is often the sign of a delusional mind.

—Lieutenant Commander Data

In this chapter:

 Variables: What are they?

 Declaring and initializing variables

 Common uses for variables

 Variables you get “for free” in Processing (a.k.a. built-in variables)

 Using random values for variables

4-1 What is a variable?

I admit it. When I teach programming, I launch into a diatribe of analogies in an attempt to explain the concept of a variable in an intuitive manner. On any given day, I might say, “A variable is like a bucket.” You put something ...

Get Learning Processing, 2nd Edition now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.