By default WordPress Media Library admin archive page shows Title, author, uploaded to, comment number and date columns. Now this tutorial explains you how you can enable it to display extra columns for Alternative Text, Caption, Description, Permalink and File URLÂ in the media library view.
So what all you have to do is install and activate Better Media Library Fields plugin and that all all, extra columns (Alternative Text, Caption, Description, Permalink and File URL) in the media library view will automatically come visible and also you can select to hide or show these new columns from the Screen Options dropdown present in the upper right corner of media library admin page. Want to know why this new plugin was made, refer to this link.