T.C.
Board certification means the physician has completed a training program after going to medical school, and they have taken certification examinations to determine their proficiency in a particular specialty.
A board certification exam is a national exam, given to doctors in a specialty to test their knowledge and experience. If a doctor fails the board exam, they can retake it at a later date.
There are good physicians who are not board certified who are practicing medicine. Likewise, there are board certified doctors who may not be good doctors. Whether the physician is board-certified or not, they would be subject to providing you with the same standard of care. Board certification (in my eyes) is a way for a physician to communicate to his/her patients that "I have gone above and beyond regarding training in this specialty, and I have passed the exams to prove it."