Bicycles can be categorized in many different ways: by function, by number of riders, by general construction, by gearing or by means of propulsion. The more common types include utility bicycles, mountain bicycles, racing bicycles, touring bicycles, hybrid bicycles, cruiser bicycles, and BMX bikes. Less common are tandems, low riders, tall bikes, fixed gear, folding models, amphibious bicycles, cargo bikes, recumbents and electric bicycles. Unicycles, tricycles and quadracycles are not strictly bicycles, as they have respectively one, three and four wheels, but are often referred to informally as bikes or cycles.
Light Reflectance Value (LRV) is the total quantity of visible and useable light reflected by a surface in all directions and at all wavelengths when illuminated by a light source. (ref.
The Lunar Roving Vehicle (LRV) or lunar rover was a battery-powered four-wheeled rover used on the Moon in the last three missions of the American Apollo program (15, 16, and 17) during 1971 and 1972.It was popularly known as the moon buggy, a play on the phrase  dune buggy .he concept of a lunar rover predated Apollo, with a 1952â1954 series in Collier's Weekly magazine by Wernher von Braun and others,  Man Will Conquer Space Soon!  In this, von Braun described a six-week stay on the Moon, featuring 10-ton tractor trailers for moving supplies.