The media tab in WordPress is where you can manage all of the media files on your website. This includes images, videos, audio files, and other types of media.
When you click on the media tab, you’ll see a list of all of the media files that you’ve uploaded to your WordPress site. You can sort and filter this list by various criteria, such as date uploaded or media type.
You can also edit and manage your media files from the media tab. For example, you can crop images, resize videos, and delete files that you no longer need. Additionally, you can insert media files into your posts and pages directly from the media library.
You can also edit the details of any file by clicking on it in the media window. From there you can add/edit Alternative Text, Titles, Captions, Descriptions, URLS, etc. To learn more about what these fields do, you can visit: https://wordpress.org/documentation/article/media-library-screen/#attachment-details