Comparing 2 Columns in Excel

I have two rather extensive columns that I need to compare. The list of numbers are different in each column (even by 10 or 15 numbers). I need to compare both columns and have the results of the differences show up in another column. Do I use Vlookup or Advanced Filter? If yes, to either question, which one is easier and how do I get the desired results.

Thank you, I am eternally grateful.

Mary.