One of the benefits of working with area type is that you can easily define the area in which the text will be contained. You can also specify many different settings as to how text will fill this defined area, which you can access by selecting an Area Type object and choosing Type > Area Type Options.
In the Area Type Options dialog, you can adjust the overall width and height of the Area Type object, as well as specify both rows and columns. The Gutter value determines the amount of space that appears between each row or column. The Inset Spacing setting determines the amount of space that appears between the border of the actual Area Type object and where the text itself begins. You can think of it like margins that are specific to this Area Type object. You can also choose from a variety of settings of where the first baseline is calculated. By specifying a text flow, you can also control if text flows from column to column or row to row. Check the Preview button so that you can preview the changes you make before you apply them.