In WordPress When working with various types of data, So you must to understand that what that data is and how it can be customized. There are five predefined post types in a default installation of WordPress:
1. Post — It is blog posts or articles and it is generally ordered by date.
2. Page — It is the hierarchical static pages of content
3. Attachment — It is use for attached to post type entries, like images and files these done by Media uploaded to WordPress.
4. Revision — It is use as a revision of a post type used as backup and can be restored if needed.
5. Nav Menus — Using the WordPress’ menu management feature it use for the Menu items added to a nav menu.
A small business website or basic blog, the above five default post types are all you might need for your work. If you have a plan on building a more complex CMS-type website, then you’ll want to utilize the power of custom post types for you work.