An author is the person who is credited with writing a post or page on WordPress. By default, the author is set to the name of the logged-in user who originally created the post or page. In some WordPress Themes, the author appears a a link to the users Gravatar biography, in others it may the biography as part of the page or post.
How to Select or Change Authors
Page and post authors may be changed from the edit screen on new pages/posts, or by editing existing ones Admin Side Bar > Posts/Pages > All Posts/Pages then click item to edit.
By default, the author selection menu is hidden. To unhide it, click Screen Options > Author. The Author Menu is now added below the Visual/Text Editor (click-and-drag the menu title to move).
To change authors, click the drop-down selection menu: Author > Selection. (Only one author selection is permitted; be sure to update or save).