Module Development Tutorial
This is a multi-step tutorial which will take you through the development of a Joomla site module. It is aimed at people who have a working knowledge of PHP and javascript, but have no experience in developing extensions for Joomla.
Along the way you'll be introduced to some key Joomla concepts.
Steps 1 to 5 cover basic functionality which will be present in most Joomla modules. We recommend that you read all these steps and try out the tutorial code in your own Joomla instance.
Steps 6 and beyond cover more advanced functionality, which you may or may not want to tackle initially.
All the code is available in the Joomla manual-examples github repository.