The top row shows the hierarchy of the previewing item, the info is composed of:

Character name > Category Name > Item Name > Current Preview Image Name.
 

Then comes the image preview area. If you are previewing a animation item, there will be a play button at the bottom left side.

Left clicking on this area, there are marking menus to helps you travel through all the items and preview images.

The middle button row:

From left to right, they are Preview Item, Next Item, Preview Image, Next Image, Set current preview images as icon.

The bottom area shows the information of the item, including the item name, author, create date, time range, etc.

also the maya related info, the controllers involved, the maya scene that the pose/animation is created, the reference asset involved.

also the modification info, if you set the icon or edit after the item is created, you gonna leave a history record here.