ULYSSIS takes backups of all files, databases, settings and repositories 1-4 times a week. These backups can be restored in case of severe server failure or in case of an emergency (if for example a user by mistake deletes all of their site). It is, however, more convenient that users take their own backups when they do experimental things on their account.
A backup of your files
You can use the graphical methods described in Accessing your files to download a copy of all of your files. This copy, or certain files, can then easily be uploaded again using the same method to restore backups
A backup of your databases
To take a backup of your database you simple use the export function of PHPMyAdmin as described on Using PHPMyAdmin.