High-definition television

High-definition television (HDTV) provides a resolution that is substantially higher than that of standard-definition television.

HDTV may be transmitted in various formats:

The letter "p" here stands for progressive scan, while "i" indicates interlaced.

When transmitted at two megapixels per frame, HDTV provides about five times as many pixels as SD (standard-definition television).

History

The term high definition once described a series of television systems originating from August 1936; however, these systems were only high definition when compared to earlier systems that were based on mechanical systems with as few as 30 lines of resolution. The ongoing competition between companies and nations to create true "HDTV" spanned the entire 20th century, as each new system became more HD than the last. Ironically, in the beginning of the 21st century, this race has continued with 4k, 5k and current 8K systems.

H.D.

Hilda "H.D." Doolittle (September 10, 1886 – September 27, 1961) was an American poet, novelist, and memoirist known for her association with the early 20th century avant-garde Imagist group of poets such as Ezra Pound and Richard Aldington. She published under the pen name of H.D..

H.D. was born in Bethlehem, Pennsylvania, in 1886 and moved to London in 1911, where her publications earned her a central role within the then emerging Imagist movement. A charismatic figure, she was championed by the modernist poet Ezra Pound, who was instrumental in building and furthering her career. From 1916–17, she acted as the literary editor of the Egoist journal, while her poetry appeared in the English Review and the Transatlantic Review. During the First World War, H.D. suffered the death of her brother and the breakup of her marriage to the poet Richard Aldington, and these events weighed heavily on her later poetry. Glenn Hughes, an authority on Imagism, wrote that 'her loneliness cries out from her poems'. She had a deep interest in Ancient Greek literature, and her poetry often borrowed from Greek mythology and classical poets. Her work is noted for its incorporation of natural scenes and objects, which are often used to emote a particular feeling or mood.

Harley-Davidson

Harley-Davidson, Inc. (H-D), or Harley, is an American motorcycle manufacturer, founded in Milwaukee, Wisconsin in 1903.

As one of two major American motorcycle manufacturers to survive the Great Depression (along with Indian), the company has survived numerous ownership arrangements, subsidiary arrangements (e.g., Aermacchi 1974-1978 and Buell 1987-2009), periods of poor economic health and product quality, as well as intense global competition— to become the world's fifth largest motorcycle manufacturer and an iconic brand widely known for its loyal following — with owner clubs and events worldwide as well as a company sponsored brand-focused museum.

Noted for a style of customization that gave rise to the chopper motorcycle style, Harley-Davidson traditionally marketed heavyweight, air-cooled cruiser motorcycles with engine displacements greater than 700 cc — and has broadened its offerings to include its more contemporary VRSC (2001) and middle-weight Street (2014) platforms.

HD

HD may refer to:

Academia

Business

Medicine