The WordPress ecosystem is gigantic, and millions of people use it daily. So, it is reasonable to assume that WordPress users use different words (terms) to describe the same things. For example, one user may say - "I have 100 orders in my database", while another says - "I have 100 posts or the order post type in my database". Both statements are correct.
We are doing our best to stay consistent with the terminology throughout the portal. We also use the italic font to emphasize these terms. So if you ever wonder what any particular term means, refer to this glossary page.
post or posts - any type of post stored in the database table
wp_options. Mentally you may think about WordPress posts, pages, orders, or contact form submissions as separate entities. However, under the hood, they are all alike and managed by WordPress core almost identically.
taxonomy - unique classifier or terms. Taxonomy is not an entity that stores in a database or any files on the server. It is a virtual classifier. A good analogy is the word car. It means nothing to you unless you can physically see and drive it. So while the car is a taxonomy that classifies the means of transportation, the car Tesla Model X with license plate XXF-0000 is the physical instance of a car.
term or terms - an instance of a specific taxonomy that is stores in the
wp_terms database table. From the real-world analogy above, the "Tesla Model X with license plate XXF-0000" is the instance of the car taxonomy.
hierarchical taxonomy - a type of taxonomy that allows creating hierarchy of terms where each child term has only one parent term. Many WordPress users call this type of taxonomy a "category".
tag or tags - a taxonomy type where all terms are on the same level. There are no parent or child terms. A good example of tags is the WordPress core "Post Tags".
backend - the WordPress CMS admin area. Any page that starts with
/wp-admin/ is part of the admin area.
frontend - any page or URL that is not part of the backend.
metabox - a small UI component on the edit screen of the backend. The official WordPress documentation describes metabox as "When a user edits a post, the edit screen is composed of several default boxes: Editor, Publish, Categories, Tags, etc. These boxes are meta boxes. Plugins can add custom meta boxes to an edit screen of any post type". Based on the recent push to use Gutenberg in WordPress, metaboxes will become obsolete. AAM will support the ability to manage access to individual metaboxes as long as WordPress core supports them.
widget - a small UI component that can render on of both backend and frontend sides. Conceptually it is very similar to the metaboxes, however, they are available only on the backend
Dashboard->Home page and on the frontend. It is also soon to become an obsolete functionality with the raise of the Gutenberg blocks.