Sacrament meeting is the main weekly gathering of the LDS Church, held on Sundays. The central feature is the sacrament ordinance (bread and water), preceded and followed by hymns, prayers, and talks given by members of the congregation. Talks are usually assigned by the bishop and delivered by lay members rather than clergy.
For Mormons, the sacrament meeting is primarily about renewing baptismal covenants and receiving encouragement to live worthily.