Pleading no contest means exactly that – you are not contesting the charges against you. Procedurally, this has the same effect as a guilty plea, but you are technically not admitting guilt to the charges. But a plea of either guilty or no contest will both result in a conviction.
There are some circumstances where it can be advantageous to plead no contest, but they are an exception rather than a rule. Your attorney will help you to determine what course of action to take in your specific case.
When you plead not guilty in a case, the burden of proof falls on the prosecution to convict you of the charges. When you plead guilty, you accept responsibility and accept the court’s decision on punishment. In a no contest plea, you accept the punishment without actually admitting guilt.