It can get frustrating when you create a new item, and you realise that you haven’t created a category yet. Joomla! 3.6 now lets you create a category on the fly for articles, contacts, newsfeeds and banners.
Joomla Categories
Categories in Joomla
In Joomla 3 you also have Categories. Each time you create an article or other content type you can assign it to a category. Categories can give you more options for structuring your content. For example you can group similar articles in one category and create a page that displays the intros of all the articles.