How to add and edit categories in WordPress

In WordPress, you can assign your posts/articles to one or more categories.
To add or edit a category, log in to the admin panel and go to Posts menu > Categories submenu.
There is a form to add new categories and a table that displays the existing ones.

The table is divided into several columns.
To hide these columns or to make it visible again, click on the Screen Options button on the upper right corner of the page and mark/unmark the corresponding checkbox.
To delete categories simultaneously, check the box in front of each name and select the Delete button from the Bulk Actions drop-down menu and click on the Apply button.
To delete a single category, hover the mouse pointer over to the name and click on the Delete button.
When you point the mouse on the name of the category, other buttons will show up.
The View button redirects you to the category page on the frontend.
The Quick Edit button lets you edit the name and slug of the category.
The Edit button displays the edit form with all the category settings.

Add and edit forms are the same. The only difference is that the add form is shown on the page with the table that displays the existing categories,
while the edit form is on a separate page.
The form has a text field for the name of the category.
That name will appear on the frontend. The page slug option is used when permalinks are enabled.
(e.g. category-name If you leave the field blank, the name will be used as slug.

On the add/edit category form, there is also a Parent drop-down menu from which you can select the parent of the category
(in case you want the particular category to be a subcategory of another one).
There is also a text area where you can type a short description.
The description may be shown at the top of the category page.