A lockset or alternatively lock set is the hardware and components that comprise the lock

Lock (device)

A lock is a mechanical or electronic fastening device that is released by a physical object or secret information , or combination of more than one of these....

ing mechanism that can usually be found on a door

Door

A door is a movable structure used to open and close off an entrance, typically consisting of a panel that swings on hinges or that slides or rotates inside of a space....

 or other hinged

Hinge

A hinge is a type of bearing that connects two solid objects, typically allowing only a limited angle of rotation between them. Two objects connected by an ideal hinge rotate relative to each other about a fixed axis of rotation. Hinges may be made of flexible material or of moving components...

 object but can also include sliding doors and dividers.
The components of a lockset can include (but are not limited to) the door handle

Door handle

A door handle is an attached mechanism used to open or close a door. In the United States, door handle can refer to any fixed or lever-operated door latch device, including on car doors. The term door knob tends to refer to round operating mechanisms.-History:The first documented invention of the...

, latch bolt, dead bolt, and decorative escutcheons of the door and can consist of mortised

Mortise lock

A mortise lock is one that requires a pocket—the mortise—to be cut into the door or piece of furniture into which the lock is to be fitted...

 or cylindrical

Cylinder lock

A cylinder lock is a lock constructed with a cylinder that a locksmith can easily unscrew to facilitate rekeying. The cylinder may contain any of a variety of locking mechanisms, including the pin tumbler lock, the wafer tumbler lock and the disc tumbler lock....

 mechanisms.
The lockset and associated hardware typically defines a door's function and how a user would (or cannot) access the two adjacent spaces defined by the opening associated with the lockset. The Americans with Disabilities Act of 1990

Americans with Disabilities Act of 1990

The Americans with Disabilities Act of 1990 is a law that was enacted by the U.S. Congress in 1990. It was signed into law on July 26, 1990, by President George H. W. Bush, and later amended with changes effective January 1, 2009....

, under Title III, and many state and local governments regulate locksets in buildings occupied by the public. Typically, locksets that employ door knob controlled latches are forbidden for public use in favor of lever handles, which are easier to operate by gravity instead of the grasping and turning required by knobs. Many municipalities also regulate locksets in terms of fire rating, using standards most often determined by Underwriters Laboratories

Underwriters Laboratories

Underwriters Laboratories Inc. is an independent product safety certification organization. Established in 1894, the company has its headquarters in Northbrook, Illinois. UL develops standards and test procedures for products, materials, components, assemblies, tools and equipment, chiefly dealing...

 in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

.

Door functions

Lockset manufacturers generally describe locksets in terms of how a door is operated by a user, while the American National Standards Institute

American National Standards Institute

The American National Standards Institute is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organization also coordinates U.S. standards with international...

, or ANSI, assigns the functioning of locksets individual alphanumerical codes also in relation to the door's operation.
For example, a "passage latch", a common industry term, on a mortised lockset is a door with a lockset consisting of two turning handles, both of which are never locked. This door function would be given the code of "F01" by ANSI. Alternatively, for a cylindrical passage latch, the ANSI code is F75.

Common Door Functions	Description	Example locations
Classroom	Outside lockable by key, inside handle always unlocked	Classrooms, commercial storage closets
Dummy	Fixed knob or lever on one side only	Decorative doors, cabinets
Passage	Rotating door handles, neither of which lock.	Residential closets
Privacy	Lockable on one side commonly by push-button, emergency release on opposite side.	Single stall or residential bathrooms, offices, bedrooms
Store Room / Vestibule	Always locked on outside requiring key for entry with rotating door handle on the inside which never locks for safe exit.	Commercial: storerooms, closets, apartment / office buildings, shared exterior entry / exit, commercial bathrooms, interior offices, fire exits, electronic strikes.