Locks and Keys

A lock secures an opening or object by means of a mechanism. A key supplies the shape, pattern or information required to operate a particular lock. Some locks use a physical key; others use a combination, card or electronic credential.

Locks add a condition to access. A door may be present and physically reachable while remaining secured. Possessing a key, finding the matching lock and being able to operate it are separate features of a situation.

Types and Characteristics

• Padlocks: Portable locks with a shackle or similar fastening that passes through another fitting.
• Door locks: Mechanisms installed within or upon a door to secure it to its frame.
• Combination locks: Operate when a specified sequence or arrangement is entered.
• Keyed locks: Use a physical key whose shape corresponds to the mechanism.
• Electronic locks: Use an electronic signal or credential to control release.
• Master-key systems: Arrangements in which some keys open a particular lock while another key opens several locks within the system.

A lock can be engaged, released, jammed or damaged. A door can also remain difficult to open after its lock has been released because something else is obstructing it. The locking mechanism is one part of the complete entrance.

Historical Background

The Science Museum Group holds a Bramah padlock and key dated 1801, identified in its collection as the challenge lock associated with the lock controversy of 1851. The paired objects place the mechanism and its intended means of operation together in the historical record. Science Museum Group: Bramah Padlock and Key

The example also offers a distinction between an object appearing secure and the question of how its security can be demonstrated. The visible exterior does not reveal every feature of the mechanism inside it.

Literary Examples

In Charles Perrault's Bluebeard, a husband gives his wife keys to his property while forbidding her to open one particular room. She enters it and discovers evidence of his previous murders. Blood on the enchanted key cannot be completely removed and reveals that she has opened the room. Charles Perrault: The Story of Blue Beard

The key serves two functions in the narrative: it allows entry and later provides evidence of that entry. The story also distinguishes the ability to open a door from permission to do so. Possession of the means of access does not remove the threat attached to using it.

Idioms and Figurative Expressions

• Under lock and key: Kept securely or closely confined.
• The key to something: The information or action considered central to understanding or achieving it.
• Unlock potential: Make previously unused capabilities available.
• Locked out: Prevented from entering or participating.
• Locked in: Confined within an arrangement or committed to a course that is difficult to change.
• Lock horns: Enter a dispute or struggle with someone.
• A key role: A position that is especially important to what happens.
• Keep something locked away: Store it securely or withhold it from others.
• Turnkey: Describes something supplied ready for use, drawing on the image of operating it by turning a key.

Homophones and Wordplay

Key / quay: A key operates a lock; a quay is a structure beside water where vessels can load or unload. In standard British pronunciation, these words sound alike.

Lock can also mean a section of hair or a chamber used to raise and lower boats between water levels. Those meanings give the word associations beyond fastening a door.

Related Pages

Doors, Gates and Thresholds, Dungeons, Containers, Ties and Binds.

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