K-line may refer to:

Chemistry

* K-line (spectrometry), one of two features in spectroscopy: **

Calcium K line In physics and optics, the Fraunhofer lines are a set of spectral absorption lines named after the German physicist Joseph von Fraunhofer (1787–1826). The lines were originally observed as dark features (absorption lines) in the optical spectru ...

, a Fraunhofer spectral line from ionised calcium **

K-line (x-ray) The K-line is a spectral peak in astronomical spectrometry used, along with the L-line, to observe and describe the light spectrum of stars. The K-line is associated with iron (Fe) and is described as being from emissions at ~6.4keV (thousand ...

, an x-ray peak in astronomical spectrometry *K line, a term used in

Internal conversion Internal conversion is a non-radioactive, atomic decay process where an excited nucleus interacts electromagnetically with one of the orbital electrons of an atom. This causes the electron to be emitted (ejected) from the atom. Thus, in interna ...

electron spectroscopy

Computing

K-line (artificial intelligence) A K-line, or Knowledge-line, is a mental agent which represents an association of a group of other mental agents found active when a subject solves a certain problem or formulates a new idea. These were first described in Marvin Minsky Marvin L ...

(Knowledge-line), a mental agent in artificial intelligence *

K-line (IRC) An IRCd, short for Internet Relay Chat daemon, is server software that implements the IRC protocol, enabling people to talk to each other via the Internet (exchanging textual messages in real time). It is distinct from an IRC bot that connects o ...

, a server ban in IRC

Finance

Candlestick chart A candlestick chart (also called Japanese candlestick chart or K-line) is a style of financial chart used to describe price movements of a security, derivative, or currency. It is similar to a bar chart in that each candlestick represents all f ...

, or K-line, a style of financial chart used to describe price movements of a security, derivative, or currency

Sports

*K line, the line marking the calculation point in

ski jumping Ski jumping is a winter sport in which competitors aim to achieve the farthest jump after sliding down on their skis from a specially designed curved ramp. Along with jump length, competitor's aerial style and other factors also affect the fin ...

Transportation

K (Broadway Brooklyn Local) The J Nassau Street Local and Z Nassau Street Express are two rapid transit services in the B Division of the New York City Subway. Their route emblems, or "bullets", are colored since they use the BMT Nassau Street Line in Lower Manhattan. ...

, earlier KK, discontinued in 1976 *

K (Eighth Avenue Local) The K Eighth Avenue Local, earlier the AA, was a rapid transit service of the New York City Subway. Its route bullet was colored on station signs, car rollsigns, and the official subway map since it ran on the IND Eighth Avenue Line. The K op ...

, a defunct train service on the New York City Subway, which was known as the AA until 1985 *

K Ingleside The K Ingleside is a light rail line of the Muni Metro system in San Francisco, California. It mainly serves the West Portal and Ingleside neighborhoods. The line opened on February 3, 1918, and was the first line to use the Twin Peaks Tunnel. ...

, a service of the San Francisco Municipal Railway sometimes called the K Line *

K Line (Los Angeles Metro) The K Line is a light rail line running north-south between the Jefferson Park and Westchester neighborhoods of Los Angeles, California, passing through various South Los Angeles neighborhoods and the city of Inglewood. It is one of seven line ...

, a light rail line in Los Angeles County, California *

K (Los Angeles Railway) K was a streetcar line in Los Angeles, California. It was operated by the Los Angeles Railway from 1913 to 1941. History The East Jefferson and 38th Street line opened on February 1, 1913. It ran from Main Street and Jefferson Avenue to East 38t ...

, defunct streetcar line in Los Angeles, California *

K Line is a Japanese transportation company. It owns a fleet that includes dry cargo ships (bulk carriers), container ships, liquefied natural gas carriers, Ro-Ro ships, tankers, and container terminals. It used to be the fourteenth largest contai ...

, a Japanese shipping company *

K-Line K-Line Electric Trains is a brand name of O gauge and S gauge model railway locomotives, rolling stock, and buildings. Formerly the brand name under which Chapel Hill, North Carolina-based MDK Inc. sold its products, K-Line was then acquired by ...

, a model railway locomotive company *

bus operator in Yorkshire, England since rebranded as Tiger Blue * Line K (Tren Interoceánico), a planned railway service in Mexico *K-Line, part of the ISO 9141

on-board diagnostics On-board diagnostics (OBD) is a term referring to a vehicle's self-diagnostic and reporting capability. OBD systems give the vehicle owner or repair technician access to the status of the various vehicle sub-systems. The amount of diagnostic inf ...

vehicle network interface standard {{disambiguation