In WordPress, the term author refers to a predefined user role. A user with author role can upload files, write, edit, publish and delete their own articles. They can also edit their profile and change their passwords.
Since a user with author role has the capability of deleting their own published posts and edit their own published articles, websites with multiple authors usually assign the contributor role to writers or use a plugin to create a user role with customized capabilities. This eliminates the risk of miscommunication, or hired writers deleting their work if they were fired.
Many websites also provide authors with author pages to give biographical information about themselves. This is usually done through the built-in author archive pages which displays a list of all posts written by them.
Some sites even display a list of authors with photos on their sidebar or their about page.
Custom information can also be displayed about them by configuring the pages to display such information. This can include things like name, date of birth, location, social profiles, and more.