- Upload - add content that is stored locally on your computer
- Web - add external content such as a YouTube video or VIUVideos URL
- Library - these are the files that you have already added to Drupal. This allows for re-use of content
Follow the dialogs after you have chosen or uploaded content and fill in the appropriate fields
- Name: this is the administration name used by Drupal and is important for locating the media for re-use (this does not need to be the file name)
- Alt Text: is used by screen readers, search engines, and when the image cannot be loaded
- Title Text: is used in the tool tip when a user hovers their mouse over the image
- Crop: allows for removing excess area of the image
- Display As: drop-down allows choice of the size of the image
When you are done hit submit to insert the image into the page.
Media/Document Alignment
Use the justification buttons to float the image to the right, left or to center it.
Media Captions
When the media is selected, the caption icon becomes active and allow you to add captions to the image.
Caption icon: 
Replace Existing Media/Document
If you want to update the media/document itself, such as the uploading a new revision of a document, it is best practice to replace the file itself. You may have multiple places in your site that link to the media, or external sites may be linked to the media. Note that you must use the same file name if you are replacing media.
To replace media use the administration toolbar to navigate to the Content view which is accessed by clicking Drupal Icon > Content on the Drupal admin toolbar. From the content view, choose the Files tab. From files tab search for the media you would like to edit (filtering on the Type and/or Site fields):
After pressing the edit button on the desired file you can change many of the fields associated with the media, as well, you can Replace file. After saving, all places that contain a reference to this media are still pointing to the correct location.