One of the most useful components to create tags in Joomla can rightly be considered an extension called TorTags.
Tags Joomla is a very useful tool for displaying similar articles and create labels website.
TorTags – the best system to create tags for your sites! This is a unique component to manage tags on the website.
Using this extension you can add tags to all components using the editor and putting them in a special box. One of the features is that the component may include tags in the content (com_content) native Joomla component, but also virtually any component, such as JoomShopping, MarketPlace, JEvents, VirtueMart, K2, JoomGallery, Joombah jobs, RedShop, Form2Content, Phoca Gallery[categories] or other simply by adding the plugin using the fields editor. In addition, labels tags can be inserted in the articles: the beginning, middle or end.
Import of meta data of articles in the tag and Vice versa
Tags for Joomla 3.0 (hereditary)