If you appear on the court date, you will be asked to enter a plea to the charge on the citation. The pleas that can be entered are: Guilty, No Contest, or Not Guilty.
Guilty - If you plead guilty, it is an admission of the charge against you.
No Contest - If you plead no contest, you declare you are neither guilty nor not guilty. The advantage of entering a no contest plea is that such plea cannot be used against you as an admission of guilt if you appear in any other court action related to the charge against you.
Not Guilty - If you plead not guilty, you deny committing the violation charged against you. The court will give you a new date to appear for trial.