Backup
As you all know, backing up cms sites is way different from doing so in a static sites, it takes more than just downloading all your files to your local computer .
Why should you backup your site?
Backups are useful in case of data loss, if your security has been compromised by malicious attackers, or simply if you made an error and would like to revert the site back to a previous state.
On this page we will teach you how to create a backup of your Joomla website. There are two parts to a complete back up of your Joomla site. First, you’ll need to download all your Joomla files to your local computer and to export the database that Joomla uses.
Database
One of the ways to backup your database is following instructions from PhpMyAdmin (common on most web hosts) or you can take a look at this tutorial.
Alternatively, there are several backup extensions for Joomla 1.5 you could look into, like JoomlaPack for a full backup of your site or SQL Dumper that can be used for both creating and restoring Joomla databases.
Joomla recommends to backup the database at least twice per week or even everyday (and more) if you have an active site.
Download all the files and folders that exist in the main directory, and save it to a folder on your local computer. This is best done with an FTP program, be it with FileZilla, which is free or with SmartFTP; and is no different than backing up a standard website.
Make sure that the file and directory structure remains the same as it is in the live site. You could then burn a CD or save to an external hard drive if you desire.