Making a Firefox extension

Intro
This section explains how to basically setup a Firefox extension.

Setting up the development Environment
Before jumping into making extensions, we must set up a development environment.

• Download and install firefox: If you haven't already done so. Download firefox and install. (Link is given on right bottom)


• Make a folder where you are going to make your Extension. Eg: D:\extension\helloworld\
  

Making the files
Install.rdf

<?xml version="1.0"?>
<RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
     xmlns:em="http://www.mozilla.org/2004/em-rdf#">

  <Description about="urn:mozilla:install-manifest">
  
    <em:id>helloworld@digitalpbk.com</em:id> 
<!-- Just an unique id of the form of an email address, need (should) not be any mail address -->
    <em:name>Hello World </em:name>
<!-- Name of the extension -->
    <em:version>1.0</em:version>
<!-- Version -->
    <em:description>Hello World Sample Extension from digitalpbk.com</em:description>
<!-- Description -->
    <em:creator>digitalpbk</em:creator>
<!--Editor name-->
    <!-- optional items -->
    <em:contributor>A person who helped you</em:contributor>
    <em:contributor>Another one</em:contributor>
    <em:homepageURL>http://digitalpbk.blogspot.com</em:homepageURL>
    <!--em:optionsURL>chrome://sampleext/content/settings.xul</em:optionsURL>
    <em:aboutURL>chrome://sampleext/content/about.xul</em:aboutURL>
    <em:iconURL>chrome://sampleext/skin/mainicon.png</em:iconURL>
    <em:updateURL>http://sampleextension.mozdev.org/update.rdf</em:updateURL-->

    <!-- Firefox -->
    <em:targetApplication>
      <Description>
        <em:id>{ec8030f7-c20a-464f-9b0e-13a3a9e97384}</em:id>
        <em:minVersion>1.5</em:minVersion>
        <em:maxVersion>2.0.0.*</em:maxVersion>
      </Description>
    </em:targetApplication>

  </Description>

</RDF>

Draft

Finally Packaging your skin
If you are familiar with Firefox, extensions are packaged in .xpi files. XPI files are compressed files and can be extracted with archiving programs like WinZip, WinRAR etc after renaming it to .ZIP .