What’s the difference between “NGC” and “PCGS”?

The Numismatic Guaranty Corporation (NGC) and the Professional Coin Grading Service (PCGS) are both third-party services that grade and certify coins. They are the two most well-known and highly respected independent coin grading companies in the U.S. All coins listed as PCGS MS70 or NGC MS70 are in Mint State Perfect condition; however, the PCGS MS70 coins were certified as such by the Professional Coin Grading Service, whereas the NGC MS70 coins were given that grade designation by the Numismatic Guaranty Corporation.