How to manage media files in WordPress
WordPress has a built-in media library for uploading and managing media files. Log in to the admin panel and go to Media tab>Library sub-tab.
This will show you a table with the existing media files (if you have any). The table itself is divided into several columns: File, Author, Uploaded to, Comments, Date. They show information corresponding to each of the uploaded files. You can remove columns from the table. To do this click on the Screen Options button in the upper right corner and unmark the respective checkbox(es).
To delete more than one file at once you can use the Bulk Actions drop-down menu. There's one above the table and another one below it. Mark the checkboxes of the files you want to delete, select Delete Permanently from the drop-down menu and click on the Apply button next to it.
To delete a single file hover the mouse pointer over its row in the table and click on the Delete Permanently button that appears. There are also a couple of other buttons. One is for viewing the page of the media file on the frontend and the other is for editing its settings. You can also go to the edit form of the file by clicking on its name in the table. To add a new media file click on the Add New button that's in the top left corner of the page, or use the one that's in the menu on the left.
You can add a media file to a post or a static page from the settings of that particular post or page. You can either use a file that you've already uploaded in the media library or you can upload a new one on the spot. For more information you can check out the tutorial on inserting media files in posts and static pages in WordPress.
For more information on the settings that can be configured on the form for adding and editing media files read the tutorial on adding and editing media files in WordPress.
For more details and screenshots on managing media files check out our WordPress media library tutorial.