A common question we receive is how to add raw HTML code to an article. Sometimes you might like to incorporate Flash, JavaScript or other HTML code into a Joomla article but find that the code is stripped or altered when you save the article. This is a safety mechanism built-in to the HTML editor to prevent you or anyone you allow to write articles containing bad or malicious code. If you are using the standard HTML editor that is supplied with Joomla, you can turn off this mechanism as follows.
We've recently updated this information for Joomla 2.5