The AJAX container is a new type of dynamic container for documents such as work items, cases, and harnesses. The AJAX container has the same purpose as a dynamic container, except that the AJAX container is not tied to any one panel of a screen layout. You can add an AJAX container directly into a section or into a cell in a dynamic layout by selecting it from the Layout menu on the section form. 

The AJAX container properties panel

The AJAX container can be a child or a sibling of a dynamic container. This flexibility in positioning allows you to display work items in areas of the screen independently of the layout. To improve page load performance, AJAX containers refresh only the content in the container. When an AJAX container is refreshed, it opens the last open document. When you submit the outer document form, a message indicates that the content in the container has been updated. 

You can select the content to display in an AJAX container by using a property reference. The AJAX container can display one or more documents.