Lava is the extrusive equivalent of magma. Magma (from Greek Î¼Î¬Î³Î¼Î±, thick unguent) is a mixture of molten or semi-molten rock, volatiles and solids that is found beneath the surface of the Earth, and is expected to exist on other terrestrial planets. Besides molten rock, magma may also contain suspended crystals, dissolved gas and sometimes gas bubbles.
United States military occupation code. A United States military occupation code, or a military occupational specialty code (MOS code), is a nine character code used in the United States Army and United States Marines to identify a specific job. In the United States Air Force, a system of Air Force Specialty Codes (AFSC) is used.
MOS Description. The machinist supervises and performs the fabrication, repair and modifications of metallic and nonmetallic parts and supervises metalworking shop activities. For more information on MOS 91E, see this Army website. National Certifications and Federal Licenses.