# Chain (disambiguation)

A chain is a series of connected links which are typically made of metal.

Chain may also refer to:

• Necklace, a jewelry which is worn around the neck
• Mail (armour) (or "chainmail"), a type of armor made of interlocking chain links
• Chain tool, small mechanical device used to "break" a bicycle chain in such a way that it could be mended with the same tool
• Chain (unit), unit of length
• Gunter's chain, a unit of measurement
• Catenary (or "chain"), the shape of a hanging flexible cable when supported at its ends and acted upon by a uniform gravitational force
• Chain (real estate), whereby a group of buyers/sellers are linked together
• Fetter (Buddhism), a deeply rooted mental attachment preventing one from achieving liberation from suffering
• Chaining, a technique from applied behavioral analysis for teaching complicated tasks by breaking them into simpler steps
• Chain Home and Chain Home Low, early British RDF (radar) systems of the WWII era
• Chains (nautical), small platforms on the sides of ships

## Management

• Chain store, retail outlets which share a brand and central management
• Chain of command, the line of authority and responsibility along which orders are passed
• Supply chain, coordinated system of organizations, people, activities, information and resources involved in moving a product or service from supplier to customer
• Cold chain, temperature-controlled supply chain
• Value chain, a management concept first described by Michael Porter

## Mathematics

• Chain (algebraic topology), formal linear combination of k-simplices
• Chain complex, a generalization of the algebraic topology construct to homological algebra
• Chain, a set paired with a total order, it usually refers to a totally ordered subset of some partially ordered set
• Markov chain, discrete-time stochastic process with the Markov property
• Pseudo-arc, which has at its heart the concept of a chain
• Chain rule, a tool for differentiation in calculus
• Conway chained arrow notation, a way of expressing exponents using arrows

## Chemistry

• Chain reaction, sequence of reactions where a reactive product or by-product causes additional reactions
• Ideal chain, mathematical model of polymer folding
• Worm-like chain (or semiflexible chain), which has Kuhn length equal to twice the persistence length

## Biology

• Food chain, a hierarchical or recursive list of predators and prey

## Economics

• Chained dollars, used to express real dollar amounts adjusted over time for inflation