Definition: PCGS stands for "Professional Coin Grading Service." PCGS is one of the two widely-recognized "top tier" grading services, the other being NGC.
See also:
What is a coin grading service?
What is coin grading?
On the Web:
Visit the PCGS Web site.
See also:
What is a coin grading service?
What is coin grading?
On the Web:
Visit the PCGS Web site.
Examples:
Personally, I prefer NGC over PCGS, but they're both equally recognized as the top-notch services for coin grading.