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optical character recognition

(Encyclopedia)optical character recognition (OCR), method for the machine-reading of typeset, typed, and, in some cases, hand-printed letters, numbers, and symbols using optical sensing and a computer. The light re...

ultraviolet radiation

(Encyclopedia)ultraviolet radiation, invisible electromagnetic radiation between visible violet light and X rays; it ranges in wavelength from about 400 to 4 nanometers and in frequency from about 1015 to 1017 hert...

Trumbull

(Encyclopedia)Trumbull, town (1990 pop. 32,016), Fairfield co., SW Conn.; settled in the 1660s, inc. 1797. Largely residential, the town has some light industry. The NASDAQ's data center is there. ...

Crestwood

(Encyclopedia)Crestwood, city (2020 pop. 11,808), St. Louis co., E central Mo., a suburb of St. Louis; inc. as a city 1949. Located in a truck-farming area, it is mos...

Medicine Hat

(Encyclopedia)Medicine Hat, city (1991 pop. 43,625), SE Alta., Canada, on the South Saskatchewan River. It is the center of a farming and ranching area with valuable natural-gas deposits that have been exploited fo...

Herndon

(Encyclopedia)Herndon, town (2020 pop. 24,655), Fairfax co., N Va., inc. 1874, rechartered 1938. A suburb of Washington, D.C., Herndon has a mix of light and high-tec...

Munster, town, United States

(Encyclopedia)Munster, town (1990 pop. 19,949), Lake co., NW Ind. It is a primarily residential suburb in the industrialized Hammond–East Chicago area. There is some light manufacturing. ...

Gloucester City

(Encyclopedia)Gloucester City, city (2020 pop. 11,484), Camden co., SW N.J., on the Delaware River, a suburb adjoining Camden and opposite Philadelphia; site of Fort ...

Amherst, city, Canada

(Encyclopedia)Amherst, town, N central N.S., Canada. Amherst has a variety of light industries and is a service center for the surrounding agricultural region. Nearby are salt beds. Across the border in...

3D printer

(Encyclopedia)3D printer, computerized device that produces a three-dimensional object by creating it as a series of thin layers. The object is created from a model stored in computer-aided design file; the model i...