Most of us don't bother pitting our own olives but should the need arise you'll know how. You'll need two dish towels and a rubber mallet. Place a clean dish towel on your cutting board and spread your olives on top - an inch or so apart will do. Cover  with a second dish towel. Now, with your rubber mallet, pound  the covered olives firmly for 10 to 20 seconds, trying not to split the pits. Remove the top towel and using your fingers press the exposed pits out of each. Repeat until finished.