Combining two lists in excel containing duplicate data

Some times we need to combine two lists.
The best way to do that is to paste the second list below the first, or first below the second, depending on which one you want to keep.
Excel keeps the first instance of any data and deletes the subsequent ones.
Now clean the data for any leading spaces etc.(see else where in this blog).
After cleaning sort the data.
The sorted data is to be filtered for unique records only by data> filter>advanced filter>unique records only.