Content Randomizer plugin utilizes its custom type posts and categories. As mentioned, it is made to separate the main content of your WordPress website from content that you want to use with Content Randomizer. Every category is a set of random content. It is more convenient way to manage and sort your random content posts.
Creation of random content categories is the same as creation of categories for WordPress posts. Just open Content Randomizer section on the WordPress admin panel sidebar and click on the sub menu item “Categories.” Now you see all available categories. You can also create new categories. Just insert category name, slug, parent category dependence (optional) and description (optional).
You can use this plugin without categories, but, as it mentioned before, it is better to use categories for sorting and managing random content.