1550s, from Middle French cube (13c.) and directly from Latin cubus, from Greek kybos a cube, a six-sided die, vertebra, perhaps from PIE root *keu(b)- to bend, turn..
The triangle illustrates the three elements a fire needs to ignite: heat, fuel, and an oxidizing agent (usually oxygen). A fire naturally occurs when the elements are present and combined in the right mixture, meaning that fire is actually an event rather than a thing. A fire can be prevented or extinguished by removing any one of the elements in the fire triangle. For example, covering a fire with a fire blanket removes the oxygen part of the triangle and can extinguish a fire.
Both modes of fire involve three essential elements: fuel, oxidizing agents (usually oxygen from the air), and a temperature high enough for the reaction to proceed (heat). In addition, the flaming mode of combustion also involves uninhibited chain reactions (collision of molecules to sustain flame continuity). In each mode all of the basic requirements must exist for the fire to start and be sustained. In most cases, flaming combustion will cease if the oxygen concentration is