Seventh-day Adventists are a Christian denomination known for their observance of Saturday, the seventh day of the week, as the Sabbath. They believe in the imminent return of Jesus Christ and emphasize health, education, and community service. Their teachings are based on the Bible, and they follow the writings of Ellen G. White, one of their founders, who is considered a prophetess. The church was established in the mid-19th century in the United States, emerging from the Millerite movement. Today, Seventh-day Adventists are active worldwide, operating schools, hospitals, and humanitarian programs, promoting a holistic approach to health and well-being.