3.2. Retaining Meaning with Datatypes
How do we store information as raw data in a computer without losing meaning? By categorizing our data and defining its datatype, we give it context that defines its meaning.
For example, suppose we have three numbers: 5155534, 5159592, and 4593030. By categorizing our data -- as, say, a phone number, fax number, and parcel tracking number -- the context (and, hence, the meaning) of our data is preserved. When categorized, each of the otherwise-nondescript seven-digit numbers becomes meaningful.
Programming languages use datatypes to provide rudimentary categories for our data. For example, nearly all programming languages define datatypes to store and manipulate text (a.k.a. strings) and numbers. To distinguish between multiple numbers, we can use well-conceived variable names, such as phoneNumber and faxNumber. In more complex situations, we can create our own custom data categories with objects and object classes as covered later. Before we think about making our own data categories, let's see which categories come built into ActionScript.
3.2.1. The ActionScript Datatypes
Every piece of data we store in ActionScript will fall into one of those categories. Before studying each datatype in Chapter 4, "Primitive Datatypes", we'll consider the general issues that affect our use of all data.
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