In Christianity, the Little Hours or minor hours are the canonical hours. The minor are those celebrated between Lauds and Vespers; they consist of Terce, Sext, Nones, and Compline. The minor hours, so called because their structure is shorter and simpler than that of the major hours, are celebrated at intervals between the major hours as a means of sanctifying the various stages of daylight and the workday.

From the time of the early Church, the practice of seven fixed prayer times have been taught; in Apostolic Tradition, Hippolytus instructed Christians to pray seven times a day "on rising, at the lighting of the evening lamp, at bedtime, at midnight" and "the third, sixth and ninth hours of the day, being hours associated with Christ's Passion." This has given rise to the practice of praying the canonical hours at seven fixed prayer times. The canonical hours are found in a book known as a breviary.

Between Lauds and Vespers, both Western Christianity (including the Roman Catholic and Lutheran traditions) and the Eastern Orthodox Church (along with the Eastern Catholic and Eastern Lutheran churches) traditionally celebrate three canonical hours, consisting mainly of psalms and bearing names derived from the hours of daylight: terce (third hour, 9 am), Sext (sixth hour, noontime) and None (ninth hour, 3 pm). These prayer times derive from ancient Jewish practice and are mentioned in the Acts of the Apostles. They also commemorate the events of the Passion of Jesus.

Chalcedonian monks later added Prime, held at the first hour of daylight. Prime is sometimes still chanted in the Eastern Catholic Churches,^{[citation needed]} but it has been suppressed in the Latin rite after the Second Vatican Council as a pairing to Lauds.

In English, the other three hours celebrated between morning and evening prayer are now in the ICEL four-volume edition of the Liturgy of the Hours called midmorning, midday and midafternoon prayer, and collectively the daytime hours; and in the three-volume edition in use in most English-speaking countries outside of the United States they are indicated as before noon, midday and afternoon, and collectively as prayer during the day.

Celebration of these three hours is in general obligatory for those who lead a contemplative life. For others, recitation of all three is recommended and, in order to preserve the tradition of praying during the day's work, those who have the duty to celebrate the Liturgy of the Hours are obliged to say at least one. The Latin collective term is hora media.

All three have the same structure. They begin with the versicle Deus in adiutorium meum intende and its response, followed by Gloria Patri and (except in Lent) Alleluia. A hymn is then said or sung, after which come the psalmody (three psalms or portions of psalms, together with their antiphons), and a short reading, followed by a versicle and a prayer. Two psalmodies are provided: one that varies from day to day for use by all, and a complementary one, with psalms chosen mainly from among the gradual psalms, for use by those who say one or two additional hours.

The text of the fixed portions of the Little Hours as used by Eastern Orthodox and Eastern Catholics of Byzantine Rite is found in the Horologion. At the Little Hours, the majority of the Office is read (actually a simple recitative—never just said with the normal speaking voice) by the reader alone, with very few variable parts. Those parts which are variable are the Troparion and Kontakion of the day. Structurally, the Little Hours are related to Compline and the Midnight Office. The structure and propers of the Little Hours are governed by the Typicon. The Little Hours are normally not read individually, but are usually aggregated with other services. The priest normally vests only in Epitrachelion (stole) and, in the Slavic practice, Epimanikia (cuffs). The Holy Doors and Curtain on the Iconostasis remain closed. The deacon does not normally serve the Little Hours.