Using the WordPress Media Library
The media library is the central location where all the files you upload to WordPress get stored. You use the media library to manage and modify those files. You can easily add descriptive titles and captions to your images, documents, and videos. The library also provides some handy tools that allow you to quickly crop, resize, and modify photos.
This screencast also walks you through the WordPress media settings, explaining how each of the settings impact the way WordPress works with the media files that you’ve uploaded.