Weighing scale
The balance (also balance scale, beam balance and laboratory balance) was the first mass measuring instrument invented. In its traditional form, it consists of a pivoted horizontal lever with arms of equal lengththe beamand a weighing pan suspended from each arm (hence the plural name ""scales" for a weighing instrument). The unknown mass is placed in one pan and standard masses are added to the other pan until the beam is as close to equilibrium as possible. In precision balances, a more accurate determination of the mass is given by the position of a sliding mass moved along a graduated scale. Technically, a balance compares weight rather than mass, but, in a given gravitational field (such as Earth's gravity), the weight of an object is proportional to its mass, so the standard masses used with balances are usually labeled in units of mass (e.g. g or kg).
History of computer animation
One of the first programmable digital computers was SEAC (the Standards Eastern Automatic Computer), which entered service in 1950 at the National Bureau of Standards (NBS) in Maryland, USA. In 1957, computer pioneer Russell Kirsch and his team unveiled a drum scanner for SEAC, to "trace variations of intensity over the surfaces of photographs", and so doing made the first digital image by scanning a photograph. The image, picturing Kirsch's three-month-old son, consisted of just 176×176 pixels. They used the computer to extract line drawings, count objects, recognize types of characters and display digital images on an oscilloscope screen. This breakthrough can be seen as the forerunner of all subsequent computer imaging, and recognising the importance of this first digital photograph, Life magazine in 2003 credited this image as one of the "100 Photographs That Changed the World".