The algorithm is a specific set of instructions/commands for solving problems. It is used in mathematics, computer science and related disciplines for calculation, data processing, etc.
Visual art that uses algorithms and computers to generate images is called algorithmic art or computer-generated art. For that purpose, algorithms are written in a programming language that allows drawing basic graphical elements like lines, curves, circles and rectangles. Algorithmic artists use precisely-defined program structures such as variables, functions, loops and mathematical operations that computer executes step by step. The obtained result is a computer-generated image displayed on a computer screen or printed on paper.
In 2010, as a part of my thesis, I used the programming language ActionScript 3.0 (part of Adobe Flash to create all kinds of fully interactive applications such as dynamic websites and computer games) for creating unique and complex images. The algorithms describe generated images, and in some cases, human input (click or mouse move) is necessary to start the program.
*Since Adobe Flash and Flash Player are no longer supported, I recorded videos of generated images.