Rating: 

I haven't? They are?

A variable stores a value, such as the text string "Hello World!" or the integer value 1. A variable can then be reused throughout your code, instead of having to type out the actual value over and over again for the entire life of the variable, which can be frustrating and tedious.

What a persuasive scenario. I'm sold.

Okay, so the level is a little too beginner for me. The paragraph on Audience could have been more helpful on this, but fine, I'll choose something more advanced.

But then, a book targeted at beginners is the last place to get sloppy with writing and editing. A quick example of the kind of carelessness that wastes a learner's time:

They can hold characters and strings, or an ordered list of characters.

This makes "an ordered list of characters" look like a third option, rather than giving a definition of a string. It would have made more sense as: They can hold characters and strings (an ordered list of characters).

Like others have said I, too, am feeling bamboozled by my blind faith in O'Reilly quality.

Oh, well. When its time is up, I'll just replace it on my Safari bookshelf with something better. Had I paid for the print version of this book, I would be pretty sad.