The media tab within OSM let's both users and network admins upload content creating a library of files for use within OSM.  

The Media tab is used for uploading and managing images, videos and flash content for use in messages.

Content can be uploaded into two locations, the shared level and the site level.  An admin can upload content by clicking the green up arrow located in the tool bar.  Choose a file from your desktop to directly upload into the media tab.

As an admin, you can upload content directly at a higher node level to make the content available to all lower site OSM users.  OSM users, can also upload content as well.

Create folders for organization by clicking the folder icon in the task bar.