The difference is the amount of jail or prison time you might serve if you are convicted of a felony, gross misdemeanor or misdemeanor. A felony is punishable by a minimum of one year in prison. A gross misdemeanor is punishable by a maximum of one year in jail. A misdemeanor is punishable by a maximum of six months in jail. No matter what you are charged with, it is critical that you hire an experienced criminal defense lawyer as early on in the process as possible.