This article is about the demographic features of the population of the Marshall Islands, including population density, ethnicity, education level, health of the populace, economic status, religious affiliations and other aspects of the population. The people of the Marshall Islands are of Micronesian origin, which is traced to a combination of peoples who emigrated from Southeast Asia in the remote past. The matrilineal Marshallese culture revolves around a complex system of clans and lineages tied to land ownership. Virtually all Marshallese are Christian, most of them Protestant (see Religion in the Marshall Islands). Other Christian denominations include Roman Catholicism, the Seventh-day Adventist Church, Latter-day Saints (LDS Church), Salvation Army, and Jehovah’s Witness. There is also a small presence of the Ahmadiyya Muslim Community and the Bahá’í Faith. Both Marshallese and English are official languages. Marshallese is spoken by most of the urban population. Both the Nitijela (parliament) and national radio use Marshallese. The public school system provides education through grade 12, although admission to secondary school is selective. The elementary program employs a bilingual/bicultural curriculum. English is introduced in the first grade. There is one post-secondary institution in the Marshall Islands—the College of the Marshall Islands.