Algorithms are a collection of step-by-step instructions used in the fields of mathematics and computer science. Computer programmers use algorithms to carry out simple tasks and calculations. Even the most complex computer programs are built from a combination of basic algorithms. By definition, algorithms must have an output, which can take the form of any unit of computer data. Also, algorithms must be finite. Programming algorithms differ depending on programing language, but all algorithms follow certain design principles, regardless of the language in which they are ultimately coded.

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Define your algorithms input. Many algorithms take in data to be processed. This data can come in the form of any unit of computer data. Most programming language will require that you specify how much input you plan to receive and what type of data that input is. For example, if you write an algorithms to calculate the area of a square, your input may be the square's height and width.

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Define the variables. Your algorithm's variables allow you to use it for more than one equation. Again using the square as an example, creating two variables as inputs for square height and width makes the algorithm applicable to any square. In other words, you can use this algorithm to determine the area of any square by inputing its height and width.

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Outline the algorithm's operations. These change the value of the input variables. Using the above example, your algorithm might multiply the height and width variables inputted earlier. This is a basic example. An algorithm's operations can take the form of multiple steps and even branch, depending on the value of the input variables.

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Output the results of your algorithm's operations. For example, if the input variables described a square with a height of 2 and a width of 3, the algorithm would output the value of 6.