Generative art is art that is created through the use of rules, systems, algorithms and processes of construction. Generative artworks can take many forms, including, images, animations, sounds, music, and even live performances. In contemporary practice, generative art is normally associated with computers and computer programming. However, this need not always be the case.

The following text introduces some of the ways in which artists create generative art. There is particular reference to artists whose work is in the Computer Arts Archive and the Leicester Computer Art Pioneers exhibition.

With the development of clockwork machines – some of which can be considered early analogue computers – it became possible to generate images and music using autonomous devices. In these cases, the rules of construction are embedded within the gears and mechanics of the device, with the clockwork mechanism enacting these rules to produce the artwork. Examples of 20th-century artists who created or adapted machines to make artworks include Desmond Paul Henry who modified a Second World War "bombsight" computer (a clockwork device) by adding pens to create a drawing machine that was capable of generating an almost infinite number of different images.

Similarly, photographer and artist Jack Tait has spent over 60 years creating electromechanical drawing machines that create pen and light drawings using a wide variety of techniques. Tait can introduce "randomness" into his processes using a mechanical "random number generator".

In 1968 an important computer art exhibition took place at the ICA in London. Curated by Jasia Reichardt, Cybernetic Serendipity brought many artists and computer scientists together to show their artwork in what was the first widely attended exhibition of its type. Much of the work was generative, including analogue and digital image-making devices. The exhibition also included robotic works, such as Edward Ihnatowicz's SAM (Sound Activated Mobile). SAM responded to participants by following simple rules that appeared to result in complex, seemingly "intelligent" behaviors.

Generative art continued to develop throughout the 1970s to the present day, with artists such as Paul Brown exploring not only the generation of static images, but the generation of animations using computational techniques such as "cellular autonoma" to create life-like moving images. Similarly, generative music became a significant art form, with generative algorithms being used to create ever-complex sounds. An important part of many generative artist's work is the use of randomness to add variety and unpredictability to their artwork.

An important figure in computer art from the 1960s until his death in 2016 was Harold Cohen. An established painter before he began to use a computer, Cohen developed a practice in which he attempted to embody the rules he used to create his artworks into a computer program he called AARON. Over a long career, he enhanced AARON to become an expert collaborator, able to generate images that he would then colorise. Cohen is regarded by some as the most important artist of the computer age.

Contemporary generative art continues to take many forms. While the principles remain the same - artworks are created by following rules - the current work can appear very different from that done by the pioneers. William Latham creates photo-realistic "organic art" that has the appearance of alien or imagined lifeforms. Andy Lomas uses the latest graphical computers to generate complex cell-like animated images that are constructed using lifelike mathematical rules. Daniel Brown (son of Paul) is known for his generated flower-like constructions that can be displayed as giant prints or screen-based animations. These artists, and more, can be found in the CAS50 Collection.

Leicester Computer Art Pioneers

The Leicester Computer Art Pioneers exhibition looks at the history of computer art creation in Leicester. Starting in the late 1960s with the artworks of Stroud Cornock and Ernest Edmonds, it traces a thread to the present day that includes Stephen Scrivener, Dominic Boreham, Brian Reffin Smith, Stephen Bell, and Sean Clark.

 Much of the work shown is generative, with a range of computer techniques and algorithms being used. As explained in the exhibition introduction, the work show is not definitive - many computer artists have lived and worked in Leicester and Leicestershire since the late 1960s. The Computer Arts Archive plans to continue researching and documenting our local computer art heritage.

Recommended Books

Available in the Computer Arts Archive

• A Computer in the Artroom by Catherine Mason

• Coded: Art Enters the Computer Age, 1952–1982 by Leslie Jones

• Digital Art by Christiane Paul

• Generative Art: A Practical Guide Using Processing by Matt Pearson