Typically we think of a description as a way of capturing the properties of a system using words (human language), thus enabling the communication of these properties between one person and another. However, an illustration, a photograph, an audio or video recording are also forms of description.

Descriptions can themselves be represented in different forms which may often be interconverted or translated to each other. For example, the word "frog" can be used as a description and the word "grenouille" can also be. A sentence can be spoken, hand written, typed, entered into a computer, stored on a computer disk, displayed on a computer screen (in different fonts, colors, etc.). Some of the issues which arise when we consider the conversion of description are: Translation between languages, encoding-decoding, compression, errors, length of description.

Since descriptions can change form, we have to be careful about distinguishing between the form and meaning of a description. However, there must still be a connection between the form and meaning, because otherwise all sentences would have the same meaning.

More generally, a description has to do with representing the properties of a system in the properties of another system (the observer). Some of the issues that arise when we think of description as representation include: Physical system representations---how patterns in physical systems are representations, and how interactions between observer and system correspond to measurements. Biological system representations---How the brain functions to represent observation, how genotype represents phenotype and vice versa, and how phenotype and genotype represent evolutionary history.

At the most basic level, a description is part of the relationship between the observers and the observed.

Related concepts: information, complexity, emergence, observer, description and complexity, meaning, observer-system relationship

 

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