The ordinance of water baptism is an outward symbol of an inner conversion that has already taken place. Therefore, most Pentecostal groups practice believer's baptism by immersion. The majority of Pentecostals do not view baptism as essential for salvation, and likewise, most Pentecostals are Trinitarian and use the traditional Trinitarian baptismal formula. However, Oneness Pentecostals view baptism as an essential and necessary part of the salvation experience and, as non-Trinitarians, reject the use of the traditional baptismal formula. For more information on Oneness Pentecostal baptismal beliefs, see the following section on Statistics and denominations.