It is usually used by taking the result of one analysis (top product sales, most popular links) and filtering a detail report to see what contributed to the ranking.
Match To – select a worksheet or previously named table from the drop down list. The worksheet must be in the same workbook, and data must start in cell A1, and it must include a header row. If you want to use a table, use the Table Name function to create the reference first.
Key Columns – select the columns that will be used to align the two tables together. The columns must have the same name in both tables, and all values from all of the selected ‘key’ columns must match for a row to match.
Ignore case – when performing the comparison, match rows even if they have differing upper or lower case letters (applies to text columns only).
Ignore spaces – when performing the comparison, match rows even if they differ because of different spacing (applies to text columns only).
Choose what to do with rows that match the other table.
Keep matching rows – keep only rows that have matching rows in the reference table.
Remove matching rows – remove rows that have matching rows in the reference table.
Blog article: Using the Match Function