Theft charges can be classified as misdemeanors or felonies, depending on the value of property stolen, where/who it was stolen from, and if there was a weapon or some form of intimidation involved in the act. Whether you will face jail or prison will be determined by the conditions of the incident, any prior criminal record you may have, and who/where you stole from.
Because of the complex nature of theft charges, it is very important to hire an experienced criminal defense attorney as soon as you can, in order to begin building a solid defense.