JS Basic
JS Introduction
JS How To
JS Where To
JS Variables
JS Operators
JS Functions
JS Conditional
JS Looping
JS Guidelines

JS Advanced
JS String Object
JS Array Object
JS Date Object
JS Math Object
JS Window
JS Form
JS Browser

JS Examples
JS Quiz Test

JS Objects

JS Books

JavaScript Guidelines

JavaScript is Case Sensitive

A function named "myfunction" is not the same as "myFunction". Therefore watch your capitalization when you create or call variables, objects and functions. 


Open symbols, like  ( { [ " ', must have a matching closing symbol, like  ' " ] } ).

White Space

JavaScript ignores extra spaces. You can add white space to your script to make it more readable. These two lines mean exactly the same:

name = "Hege"

Break up a Code Line

You can break up a code line within a text with a backslash. The example below will be displayed properly:

document.write("Hello \

Note: You can not break up a code line like this:

document.write \
("Hello World!")

The example above will cause an error.

Insert Special Characters

You can insert special characters (like " ' ; &) with the backslash:

document.write ("You \& I sing \"Happy Birthday\".") 

The example above will produce this output:

You & I sing "Happy Birthday".


You can add a comment to your JavaScript code starting the comment with "'//":

sum=a + b  //calculating the sum

You can also add a comment to the JavaScript code, starting the comment with "/*" and ending it with "*/"

sum=a + b  /*calculating the sum*/

Using "/*" and "*/" is the only way to create a multi-line comment:

/* This is a comment
block. It contains
several lines*/