St. Teresa of Lisieux, also known as the "Little Flower," was a French nun born on January 2, 1873. She joined the Carmelite Order at a young age and dedicated her life to prayer and service. Teresa is best known for her spiritual writings, particularly her autobiography, "Story of a Soul," which outlines her "little way" of achieving holiness through simple acts of love and trust in God. She passed away on September 30, 1897, at the age of 24, and was canonized as a saint by Pope Pius XI in 1925. St. Teresa is the patron saint of missions and is celebrated for her deep spirituality and influence on modern Catholicism. Her feast day is observed on October 1.