Sharing elements from one page to the next allows you to edit information on one element and it will change it on all of the elements that are sharing that content.  Many use this for their address information.  That way it can be copied from one element to many elements on the page.

How to:

1. Login to your site.
   
2. Click on the Add Element button.
   
3. Click on the link that says "copy an element from another part of your site."
   
4. Click on the dropdown to reveal pages and the elements on them.
   
5. Click on the page and element you would like to share to the page you are on from the dropdown menu.
6. Click the Add button.
   

Note: Information you change in any of the shared elements will be changed on all of them.  If you have an element that you no longer want to be shared, you will need to delete it and add it back as a new element, not shared.