Algorithm
The word 'algorithm' has its roots in Latinizing the name of Muhammad ibn Musa al-Khwarizmi in a first step to "algorismus". Al-Khwārizmī (, , c. 780–850) was a Persian mathematician, astronomer, geographer, and scholar in the House of Wisdom in Baghdad, whose name means 'the native of Khwarezm', a region that was part of Greater Iran and is now in Uzbekistan.
Technologies in 2001: A Space Odyssey
Clarke noted that, contrary to popular rumor, it was a complete coincidence that each of the letters of Hal's name immediately preceded those of IBM in the alphabet. The meaning of HAL has been given both as "Heuristically programmed ALgorithmic computer" and as "Heuristic ALgorithmic computer". The former appears in Clarke's novel of "2001" and the latter in his sequel novel "2010". In computer science, a heuristic is a programmable procedure not necessarily based on fixed rules, producing informed guesses often using trial-and-error. The results can be false such as in predictions of stock market, sports scores, or the weather. Sometimes this can entail selecting on-the-fly one of several methods to solve a problem based on previous experience. On the other hand, an algorithm is a programmable procedure that produces reproducible results using invariant established methods (such as computing square roots).
A heuristic approach that usually works within a tolerable margin of error may be preferred over a perfect algorithm that requires a long time to run.