A calculation is a deliberate process that transforms one or more inputs into one or more results, with variable change. The term is used in a variety of senses, from the very definite arithmetical calculation of using an algorithm, to the vague heuristics of calculating a strategy in a competition, or calculating the chance of a successful relationship between two people. For example, multiplying 7 by 6 is a simple algorithmic calculation. Estimating the fair price for financial instruments using the Black–Scholes Black–Scholes model is a more complex algorithmic calculation. Statistical estimations of the likely election results from opinion polls also involve algorithmic calculations, but produces ranges of possibilities rather than exact answers. To calculate means to ascertain by computing.[citation needed] The English word derives from the Latin Latin calculus, which originally meant a small stone in the gall-bladder (from Latin Latin calx). It also meant a pebble used for calculating, or a small stone used as a counter in an abacus ( Latin Latin abacus, Greek abax). The abacus was an instrument used by Greeks and Romans for arithmetic calculations, preceding the slide-rule and the electronic calculator, and consisted of perforated pebbles sliding on iron bars.Contents1 Comparison to computation 2 See also 3 References 4 External linksComparison to computation Calculate comes from the Greek word Κάχληκα or gravel in English because Greeks used gravel for counting. Calculation is a prerequisite for computation. The difference in the meaning of calculation and computation appears to originate from the late medieval period. See alsoLook up calculation in Wiktionary, the free dictionary.Thinking portalAbacus Calculator Calculus (other) Calculability Computation Cost accounting List of algorithms Mathematics Mental calculationReferences^ http://science.jrank.org/pages/7536/Calculation-Computation.html ^ http://science.jrank.org/pages/8509/Calculation-Computation-Premodern-Early-Modern-Non-Western.htmlExternal links"The Lifting of the Veil in the Operations of Calculation" is a manuscript, from the 18th-century, in Arabic, by Ibn al-Banna' al-Marrakushi, about calculation processesAuthority control