EDDY Apprentice. Whats the difference between CNC and NC machine and do u people know any institute which teaches CNC programming. #1 Jul 24, 2009. Aashish Joshi Maniac. Engineering Discipline: Mechanical. In a Numerical Control machine, the program is fed to the machine through magnetic tapes or other such media.
A volcano is a vent or chimney which transfers molten rock known as magma from depth to the Earth's surface. Magma erupting from a volcano is called lava and is the material which builds up the cone surrounding the vent. A volcano is active if it is erupting lava, releasing gas or generates seismic activity.
1 Most of the caves in the world-as well as the largest-are of this type.  lava caves are tunnels or tubes in lava formed when the outer surface of a lava flow cools and hardens while the molten lava within continues to flow and eventually drains out through the newly formed tube.