You will notice that the assets in your Lightbox that you have permission to download are selectable by clicking on the 'Select Item' checkbox at the top of each asset. Once you have selected some assets you can then perform actions on them using the drop down box:

The actions you can perform are as follows (note: you may not see all of these actions depending on your permissions as a user):

Download

This is the same process as downloading your lightbox, except the system will create a zip file of only the currently selected assets.

Print or compare images

Allows you to see assets and their attributes side by side for comparison, and enables you to print out a contact sheet of the selected images. Find out more.

Note: this only works for assets that are images.

Remove from My Lightbox

Removes the selected assets from your Lightbox. 

Bulk Update

Allows you to perform a Bulk Update on the selected assets.

Link items

This will make all the selected assets related items. This means that when viewing the details of any of these assets you will find links to all of its related items.

Export items

Available to admin users, org unit admin users (if  org-unit-admins-can-export is true) and any users that are in a group that has been ticked as 'can export assets'. Takes the selected assets and offers the user the ability to export their metadata and (optionally) files.

Copy or move items

This will allow all the selected assets to me copied or moved to another lightbox.