Essential ASP for Web Professionals

Data Types

JavaScript is loosely typed, which means that, unlike many programming languages, there is a lot of flexibility in terms of how variables are used.

Note that all JavaScript datatypes sometimes act like objects, whether it's a string that can have a method applied to it or a Boolean that can be created using a constructor. That's part of JavaScript's charm.

Strings

Strings are the most generic data type, consisting of zero or more characters that can be concatenated and parsed in a few ways. For example:

greeting = "Hello World"

creates a variable called greeting with a value of "Hello World."

The first time you use a variable, you can optionally declare it. It's also a good practice to put a semicolon at the end of a line:

 var greeting ...