Programming Visual Basic 2008

Chapter 6. Data and Data Types

Data is a funny word—although not as funny as datum. Our minds are filled with data: the useful and useless trivia that clogs thought; the millions of memories that keep superficial conversations going strong. But the word data rarely comes up in conversation. Unless you are a computer junkie, or you hang around the office all hours of the day or night waiting for reports of crunched numbers, you never have a need to use the term. I have never been asked to lend someone a cup of data. My friends never try to judge my health by asking, “How’s your data going?” And you almost never hear it used as a character name in popular science fiction television shows.

Despite its lack of usage in everyday communication, data is extremely important. In the programming world, it is everything. In this chapter, we will discuss how Visual Basic uses and manipulates data within your applications, and how you can master the tools that make this manipulation possible.

The Nature of Computer Data

In Chapter 2, I mentioned how all data in a computer eventually breaks down to individual bits, electrical impulses that represent either 1 or 0, on or off, true or false. Since our decimal number system requires more than just those two values, computers work in the world of binary—a number system limited to only the numbers 0 and 1. Fortunately, it’s pretty easy to represent basic decimal integer numbers using binary notation. You probably remember Mrs. Green back in second grade ...