Do I have to appear in court?
It depends. If you do not have an attorney then you are always required to appear.
If you were charged with a class C misdemeanor (this includes traffic tickets) then your attorney can usually handle all required appearances for you except trial.
If you were charged with a class B or A misdemeanor or any level of felony offense, then you will be required to appear in court. Your attorney may be able to handle some of those appearances for you but you should always assume that your attendance is required unless your attorney specifically tells you otherwise. The same is true for offenses prosecuted in federal court.
If you fail to appear when required, the court may forfeit your bond, charge you with failure to appear or bail jumping, and issue a warrant for your arrest.