Very Basic: How to remove items in one list from another list?

This is a very basic question, but it's been bugging me.

Say I have an Excel file with two columns. The first column, let's call it "NAME1", has values that I want to remove from the second column "NAME2". My excel file has column names and I have set this to "TRUE" in the Excel Reader component.

What's the most efficient way to go about doing this using Pilotscript? My issue is mainly with terminology and data handling. I'm coming from an Actionscript and PHP background, so I'm still feeling out the difference between the data types in P.P.

Thanks! Smiler