The source columns allow you to configure which columns appear at the left-had side of the table.
produces a table like this:
In this case, we have chosen to print two source columns: the Name and Alias attributes.
You can configure the order in which they appear by using the UP and DOWN buttons.
So changing the order of the columns to show the Alias, then the Name, the screen would look like this:
producing a table like this:
Adding a title to the columns produces a table like this: