True to the Faith, (2004), 81

Latter-day revelations speak of hell in at least two ways. First, it is another name for spirit prison, a place in the postmortal spirit world for those who have “died in their sins, without a knowledge of the truth, or in transgression, having rejected the prophets” (D&C 138:32). This is a temporary state in which spirits will be taught the gospel and have the opportunity to repent and accept ordinances of salvation that are performed for them in temples (see D&C 138:30–35). Those who accept the gospel may dwell in paradise until the Resurrection. After they are resurrected and judged, they will receive the degree of glory of which they are worthy. Those who choose not to repent but who are not sons of perdition will remain in spirit prison until the end of the Millennium, when they will be freed from hell and punishment and be resurrected to a telestial glory (see D&C 76:81–85).

Second, the word hell is used to refer to outer darkness, which is the dwelling place of the devil, his angels, and the sons of perdition (see D&C 29:36–38; 76:28–33). Sons of perdition are those who receive “no forgiveness in this world nor in the world to come—having denied the Holy Spirit after having received it, and having denied the Only Begotten Son of the Father, having crucified him unto themselves and put him to an open shame” (D&C 76:34–35; see also verses 31–33, 36–37). Such individuals will not inherit a place in any kingdom of glory; for them the conditions of hell remain (see D&C 76:38; 88:24, 32).