A "record selection" means the records that appear in the list window. While
there may be a hundred records available, you may only have six listed. In that
case your record selection would be six records. If all one hundred records
were listed, your record selection would be one hundred records. When you first
open the List Members window, all the records will be listed.
There may be times when you will want to limit your record selection. For example, if you were to print some labels, the labels would only be generated for every record in your selection, not every record in the file. The same principle applies to the Quick Reports: it will report only on the records in your selection.
One way to limit your selection is to search for the records you want.