Joomla plugin development

This article is about the development of a custom Joomla plugin. This might become important to add a specific functions to your Joomla website.
Joomla plugins are powerful tools with a wide set of applications. A very common task for instance is to manipulate the Joomla output just before it is displayed on the website. I would like to develop this idea further and write a Joomla Plugin that modifies the output before Joomla content is displayed. You might remember our custom Joomla component "com_smartphones" which displays different smartphones in the Joomla frontend. We could think of a Joomla Plugin that goes through a Joomla article, checks if it contains the name of a smartphone stored in the database and adds automatically a link to the smartphone page. Within the following I will develop exactly such Joomla plugin.