Learn Enough JavaScript to Be Dangerous: Write Programs, Publish Packages, and Develop Interactive Websites with JavaScript

Chapter 4

Other Native Objects

Now that we’ve taken a look at strings and arrays, we’ll continue with a tour of some other important JavaScript objects: math, dates, regular expressions, and generic objects.

4.1 Math and Number

Like most programming languages, JavaScript supports a large number of mathematical operations:

> 1 + 1;
2
> 2 - 3;
-1
> 2 * 3;
6
> 10/5;
2 > 2/3;
0.6666666666666666

Note that the final example here isn’t exact; it’s a floating-point number (also called a float), which can’t be represented exactly by the computer. But in fact JavaScript has only one numerical type, and even something like 1 or 2 is treated as floating point under the hood. This is convenient for us as programmers, since it means we never have to make ...