Technology is a broad concept that deals with a species' usage and knowledge of tools and crafts, and how it affects a species' ability to control and adapt to its environment. In human society, it is a consequence of science and engineering, although several technological advances predate the two concepts. Technology is a term with origins in the Greek "technologia", "τεχνολογία" — "techne", "τέχνη" ("craft") and "logia", "λογία" ("saying"). However, a strict definition is elusive; "technology" can refer to material objects of use to humanity, such as machines, hardware or utensils, but can also encompass broader themes, including systems, methods of organization, and techniques. The term can either be applied generally or to specific areas: examples include "construction technology", "medical technology", or "state-of-the-art technology".
The human race's use of technology began with the conversion of plentiful natural resources into simple tools. The prehistorical discovery of the ability to control fire increased the available sources of food, and the invention of the wheel helped humans in travelling in and controlling their environment. Recent technological developments, including the printing press and the Internet, have lessened physical barriers to communication and allowed humans to interact on a global scale. However, not all technology has been used for peaceful purposes; the development of weapons of ever-increasing destructive power has progressed throughout history, from clubs to nuclear bombs.
A nuclear weapon is a weapon which derives its destructive force from nuclear reactionss of fission or fusion. As a result, even a nuclear weapon with a small yield is significantly more powerful than the largest conventional explosives, and a single weapon is capable of destroying an entire city.
In the history of warfare, nuclear weapons have been used only twice, both during the closing days of World War II. The first event occurred on the morning of August 6, 1945, when the United States dropped a uranium gun-type device code-named "Little Boy" on the Japaneseese city of Hiroshima. The second event occurred three days later when the United States dropped a plutonium implosion-type device code-named "Fat Man" on the city of Nagasaki. The use of these weapons, which resulted in the immediate deaths of around 100,000 to 200,000 people and even more over time, was and remains controversial.
Gas metal arc welding (GMAW), sometimes referred to by its subtypes, metal inert gas (MIG) welding or metal active gas (MAG) welding, is a semi-automatic or automatic arc welding process in which a continuous and consumable wireelectrode and a shielding gas are fed through a welding gun.
At the beginning of the Apollo program Kraft retired as a flight director in order to concentrate on management and mission planning. In 1972 he became director of the Manned Spacecraft Center (later Johnson Space Center), following in the footsteps of his mentor Robert Gilruth. He held the position until his retirement from NASA in 1982. During his retirement, Kraft has consulted for numerous companies including IBM and Rockwell International, and he published an autobiography entitled Flight: My Life in Mission Control.
