Here are my M&Ps, one of which we received as a gift for our wedding and the other we purchased shortly thereafter falling in love with the first one:
To refer to it properly, the Mortar is the bowl shape and the Pestle is the handle-like tool. Color and sizes may vary, but the basic conceptual shape always remains the same. Originally the Mortar and Pestle were used by Apothecaries to grind up medicines, roots, herbs, and the like. They served the scientific purpose of remedial health. Nowadays, they have since gained ground in the kitchen for milling spices and such. And let's face it, sometimes a recipe can be a bit of a science, so it is a fitting transition for this handy tool to make its way to the kitchen counter.
In our household we use our dark grey M&P for grinding Sea salt, and our white M&P for grinding black pepper. Having such freshness on hand adds great flavor to any dish, and adds a bit of a workout for the day! Double bonus (just kidding). Highly recommended.