How do I start/setup Selenium for recording as well as running in different browsers and platforms?

Can anyone please give me a tutoial on How to stat or setup Selenium for recording as well as running in different browsers and platforms?

Steps 1) Launch Firefox and navigate to https://addons.mozilla.org/en-US/firefox/addon/selenium-ide/. Click on Add to Firefox

Steps 2) Wait until Firefox completes the download and then click “Add.”

Steps 3) Once install is complete, you will get a confirmation message. Click “OK”

Steps 4) Click on the Selenium IDE icon

Selenium IDE will open

Selenium is an automation testing tool used to automate various types of applications. It consists of three main parts Selenium IDE, Selenium RC & Selenium WebDriver. In today’s date the WebDriver is the latest version of the Selenium.

WebDriver is a web automation framework that allows you to execute your tests against different browsers, not just Firefox, Chrome (unlike Selenium IDE).

WebDriver also enables you to use a programming language in creating your test scripts (not possible in Selenium IDE).