What you should already know
This guide assumes you have the following basic background:
- A general understanding of the Internet and the World Wide Web (WWW).
- Good working knowledge of HyperText Markup Language (HTML).
|Object-oriented. No distinction between types of objects. Inheritance is through the prototype mechanism, and properties and methods can be added to any object dynamically.||Class-based. Objects are divided into classes and instances with all inheritance through the class hierarchy. Classes and instances cannot have properties or methods added dynamically.|
|Variable data types are not declared (dynamic typing).||Variable data types must be declared (static typing).|
|Cannot automatically write to hard disk.||Can automatically write to hard disk.|
The ECMAScript specification is a set of requirements for implementing ECMAScript; it is useful if you want to implement standards-compliant language features in your ECMAScript implementation or engine (such as SpiderMonkey in Firefox, or V8 in Chrome).