In woodworking or metal fitting, a lap joint is a technique for joining two pieces of material by overlapping them. A lap may be a full lap or half lap. In a full lap, no material is removed from either of the members to be joined, resulting in a joint which is the combined thickness of the two members. In a half lap joint, material is removed from each of the members so that the resulting joint is the thickness of the thickest member. Most commonly in half lap joints, the members are of the same thickness and half the thickness of each is removed.

Half lap joints are used extensively in construction and cabinetry for framing. They are quick and easy to make and provide reasonable strength through good long grain to long grain gluing surface. The shoulders provide some resistance to racking (diagonal distortion). They may be reinforced with dowels or mechanical fasteners to resist twisting.

Also known simply as a 'pull lap', it is the basic form of the lap joint and is used when joining members end to end either parallel or at right angles. When the joint forms a corner, as in a rectangular frame, the joint is often called a corner lap. This is the most common form of end lap and is used most in framing.

A lap is a surface created between the knee and hips of a bipedal being when it is in a seated or lying down position.

There are numerous consumer devices created specifically for use with the lap. The laptop, for example, was designed for people who required the use of a computer when away from their usual work space. As portable computers grew smaller, some evolved into "notebooks", in reference to their small physical size, instead of its possible positioning during use.

An earlier consumer product designed for the lap was the lapdog. A small dog, usually a terrier, which was bred to sit in the lap of a wealthy or fashionable European woman.

In some forms of the Christmas tradition, young children sit upon the lap of Santa Claus to tell him what gifts they would like. Around the Christmas buying season each year, many malls, especially those in North America are known to offer an area where parents can bring their children to partake in this tradition.

A "lap dance" is an erotic dance and sexual act. It is commonly performed as a paid service by exotic dancers to their clientele. A lapdance is performed by one person straddling the lap of the other and gyrating their lower extremities in a provocative manner.

A joint is the location at which two or more bones make contact. They are constructed to allow movement (except for skull bones) and provide mechanical support, and are classified structurally and functionally.

Joints are mainly classified structurally and functionally. Structural classification is determined by how the bones connect to each other, while functional classification is determined by the degree of movement between the articulating bones. In practice, there is significant overlap between the two types of classifications.

Terms ending in the suffix -sis are singular and refer to just one joint, while -ses is the suffix for pluralization.

Structural classification names and divides joints according to how the bones are connected to each other. There are three structural classifications of joints:

Joints can also be classified functionally, by the degree of mobility they allow:

Joints can also be classified based on their anatomy or on their biomechanical properties. According to the anatomic classification, joints are subdivided into simple and compound, depending on the number of bones involved, and into complex and combination joints: