title: Sum
text: # Sum
  
  Sum most commonly means the total of two or more numbers added together; see addition.
  
  Sum can also refer to:
  
  ## Mathematics
  
  * Sum (category theory), the generic concept of summation in mathematics
  * Sum, the result of summation, the addition of a sequence of numbers
  * 3SUM, a term from computational complexity theory
  * Band sum, a way of connecting mathematical knots
  * Connected sum, a way of gluing manifolds
  * Digit sum, in number theory
  * Direct sum, a combination of algebraic objects
     * Direct sum of groups
     * Direct sum of modules
     * Direct sum of permutations
     * Direct sum of topological groups
  * Einstein summation, a way of contracting tensor indices
  * Empty sum, a sum with no terms
  * Indefinite sum, the inverse of a finite difference
  * Kronecker sum, an operation considered a kind of addition for matrices
  * Matrix addition, in linear algebra
  * Minkowski addition, a sum of two subsets of a vector space
  * Power sum symmetric polynomial, in commutative algebra
  * Prefix sum, in computing
  * Pushout (category theory) (also called an amalgamated sum or a cocartesian square, fibered coproduct, or fibered sum), the colimit of a diagram consisting of two morphisms f : Z → X and g : Z → Y with a common domainor pushout, leading to a fibered sum in category theory
  * QCD sum rules, in quantum field theory
  * Riemann sum, in calculus
  * Rule of sum, in combinatorics
  * Subset sum problem, in cryptography
  * Sum rule in differentiation, in calculus
  * Sum rule in integration, in calculus
  * Sum rule in quantum mechanics
  * Wedge sum, a one-point union of topological spaces
  * Whitney sum, of fiber bundles
  * Zero-sum problem in combinatorics
  
  ## Computing and technology
  
  * Sum (Unix), a program for generating checksums
  * StartUp-Manager, a program to configure GRUB, GRUB2, Usplash and Splashy
  * Sum type, a computer science term
  
  ## Art and entertainment
  
  * Sum, the first beat (pronounced like "some") in any rhythmic cycle of Hindustani classical music
  * "Sum", a song by Pink Floyd from The Endless River
  * Sum: Forty Tales from the Afterlives, a 2009 collection of short stories by David Eagleman
  * Sum 41, a Canadian punk band
  * SUM, the computer in Goat Song (novelette) story by Poul Anderson in Magazine of Fantasy and Science Fiction, (1972).
  
  ## Organizations
  
  * Senter for utvikling og miljø (Centre for Development and the Environment), a research institute which is part of the University of Oslo
  * Soccer United Marketing, the for-profit marketing arm of Major League Soccer and the exclusive marketing partner of the United States Soccer Federation
  * Society for the Establishment of Useful Manufactures, a now-defunct private state-sponsored corporation founded in 1791 to promote industrial development along the Passaic River in New Jersey in the United States
  * The State University of Management, a Russian university
  * Save Uganda Movement, a Ugandan militant opposition group
  
  ## Places
  
  * Sum (administrative division), an administrative division in Mongolia, China, and some areas of Russia
     * Sum (Mongolia), an administrative division of Mongolia
  * SUM, the IATA airport code for the Sumter Airport in Sumter County, South Carolina, U.S.
  
  ## Other uses
  
  * Sum, an old name for the Finns in East Slavic languages, derived from the word Suomi, "Finland"
  * Soum (currency) (also spelled "sum"), a unit of currency used in some Turkic-speaking countries of Central Asia
  * SUM (interbank network), an interbank network in 42 U.S. states
  * SUM, the ISO 639-3 code for the Sumo language
  * Cen (surname), sometimes Romanized Sum
  * Cogito, ergo sum, Latin for: "I think, therefore I am"
  * Sum certain, a legal term
  