As Joomla! is an open source content management system(CMS), it can subject to a great number of various hacking attacks. That`s why it is very important to improve Joomla security every day and use all possible methods for this. Follow the instructions bellow and you will get essential knowledge in Joomla security and, how not to be attacked by hackers.
Get more here: http://www.balbooa.com/knowledgebase/41-documentation-joomla-security/216-joomla-security-checklist
Will be posted after admin approval.