From Joomla! Documentation
As someone who has not used Joomla! before, you need to know how to get started. Maybe you have a friend or a neighbour who uses Joomla! and you want a Joomla! web site of your very own. Maybe you have a small business or a club or a community that needs a web presence, and you want to use Joomla! for that purpose. Maybe you are a seasoned Information Technology professional, but you have never used Joomla! before. If so, you are just starting a very enjoyable journey and we warmly welcome you to Joomla!