Key

Key may refer to:

• Key (lock), device used to open a lock or door
• Key (cryptography), a piece of information that controls the operation of a cryptography algorithm (see Subkey)
• Key (engineering), a type of coupling used to transmit rotation between a shaft and an attached item

Biology

• Single-access key, a method used for categorizing species using logical choices

Computing

• Computer keyboard keys
• KeY, a software verification tool
• Unique key, a set of fields that uniquely identify any record in a database or registry
• Superkey, a similar concept or idea
• Candidate key, a minimal superkey
• Keychain (Mac OS), the Apple-created utility for the Macintosh that stores passwords
• Key, which make up the key-value pairs of a hash table
• .key, file extension used by Keynote

Fiction

• Key (comics), a DC Comics supervillain
• Key (Marvel Comics), a fictional mutant character
• Key the Metal Idol, Japanese anime OVA series

Places

• Key Island, Tasmania, Australia
• Florida Keys, an archipelago of about 1700 such islands in the southeast United States

Music

• Key (instrument), musical instruments have keys for tuning and keys for playing; such as on a guitar
• Key (music), a set of notes in music
• Key (singer) (born 1991), South Korean entertainer
• Key (album), an album by Son, Ambulance
• Key signature, in musical notation and tablature
• Keys can be short for keyboards, a type of musical instrument part of the percussion family

Surnames

• Key (surname)
• Keys (surname)
• Keyes (disambiguation)

Other uses

• Cay, a small, low island
• Chroma key, a method to superimpose several video layers using areas of a defined color as a mask
• Churchkey, various kinds of bottle and can openers
• Clef (from the French for "key"), the symbol that assigns note names to the lines and spaces of the musical staff
• Greek key pattern, a meander pattern
• House of Keys, the directly elected lower branch of Tynwald, the parliament of the Isle of Man
• Identification key, a method of deducing the correct species assignment of a living thing
• KeyBank, a bank headquartered in the Key Tower in Cleveland, Ohio
• Key (basketball), also known as the shaded lane in a basketball court
• Keychain, small chain that connects a small item to a keyring
• Key (chart), a guide to colours and symbols used in a data chart, graph, plot or diagram
• Key Club, a worldwide student service organization
• Key color (typically black), in the CMYK color model
• Key (company), a Japanese visual novel studio
• Key frame, a frame made by an animator from which other frames are derived
• Key light, the primary light source that illuminates an image or scene
• Keyline, a dark line separating color elements in four-color printing
• Key (map), a guide to a map's symbology
• Key or legend, an explanation of the symbols and colours used in a diagram
• Key plate, a plate which prints the detail in an image, often using the color black
• Keys, a truce term used in western Scotland
• Keystone (architecture), the stone at the apex of an arch that holds the arch in place
• Kirby's Epic Yarn, a 2010 game by Nintendo
• Quay
• Samara (fruit) or key, a type of fruit in which a flattened wing of fibrous, papery tissue develops from the ovary wall
• Skeleton key or Master key, a key altered to bypass wards placed inside a lock
• Subkey
• Telegraph key, the button used by a telegraph operator
• The Key (disambiguation)

See also

• Keying (disambiguation)