Explain the concept of community corrections and why it is different than traditional confinement options for convicted criminal offenders.

The concept of community corrections is to place an offender under a program of supervision, with determined rules and boundaries to adhere to, that is outside of the confinements of prison.
When serving a custodial sentence, an offender will be confined to a prison setting and therefore lose the freedom to move around and interact with the community. This is particularly important in the case of violent offenders or murderers who pose a threat to the community and therefore need to be removed from it altogether to safeguard others. This is sometimes done with a view to rehabilitation over time or, in the worst cases, for an indefinite term to ensure the safety of the community.
Where community corrections differ is that offenders, whilst still under the supervision of authority, are not placed in confinement. It can therefore only be considered for people who aren't likely to cause harm or re-offend.
Community corrections take the from of two common programs: parole and probation. In the case of parole, an offender may be eligible for release from prison before the completion of their sentence. It can therefore be used as an incentive to reward good behavior, or even as an option to release prisoners on compassionate or medical grounds in certain circumstances.
In the case of probation, offenders can be allowed to complete sentences that include rules and restrictions but do so within their communities rather than within the confinements of prison. This may require an offender to meet regularly with a probation officer to confirm their whereabouts or even take tests to prove they are refraining from drugs.
Community correction is used where it is the interests of both the offender and the community that their rehabilitation takes place outside the confinements of prison. However, the expectations placed upon offenders means they are still serving a sentence, with conditions that make a custodial sentence likely if they fail to comply.