Y
This article is using the List template and is configured to show metadata articles only in a 1-column grid.
The List template has been employed here to implement an A to Z "letter" page. It has body text just like a Default but also displays a list of metadata articles in a 1-column grid. It relates the single metadata value Alphabetic Metadata Relations=Y and, as a result, displays all articles that also relate this same value.
The ordering of the metadata articles has been set (somewhat understandably) to "Item Heading A-Z", and the maximum number of items per page has been set to 10. For "Summary View" (where this article may appear as an item in another list) it has been set to display the first 5 listable items. To see this in action simply visit this article's parent, Listing pages.
For more information please view our online documentation: List template.