A “U” in an “O” (i.e. a circle), is the kosher symbol for the Orthodox Union, the largest (by far) kosher cerifying agency in the United States. That symbol on a food product, indicates the product is kosher. The “P” next to the O-U symbol means the food product is not just kosher all-year round, but it is even Kosher-for-Passover use. (The 8 days of Passover has much more stringent kosher requirements.)
The “pareve” designation indicates it has no dairy or meat in the food product (and this can be consumed with either dairy or meat products.)