The layout style is the way in which the data will be displayed by the browser. You can select one of these when you define the external set. There are four possible layouts available:
A table shows the data in columns, for example:
A form is a set of vertical tables, like this:
A list is just a list of the data, with breaks between each record, like this:
This is similar to a list, but has a different layout, as shown here:
You can use more than one layout style for different sets in the same export task.