Probation is for offenders who serve their sentences under community supervision, generally instead of incarceration.
Parole is for offenders who have been conditionally released from prison to serve the rest of their sentence in the community. The state Parole Board determines which offenders are eligible to be released on parole.
Parolees and Probationers must both abide by conditions set either by the sentencing court or the Parole Board. These conditions can include the payment of fines or court costs, participation in treatment for mental health or substance abuse, random drug testing, and regular meetings with a probation officer.
Failure to comply with these conditions can result in sanctions, up to and including revocation. Revocation usually requires offenders to serve the remainder of their sentence incarcerated, either in jail or with the state Department of Correction.