High- and low-level

High-level and low-level are typically terms used to classify, describe and point to specific goals of a systematic operation, though its uses also vary depending on the context - such as use in computer science versus business administration. In general, high-level is used to describe operations that are more abstract in nature, where overall goals and systemic features are typically more concerned with the wider, macro system as a whole. Alternatively, a low-level description is one that describes more specific individual components of a systematic operation, focusing on the details of rudimentary micro functions rather than macro, complex processes. Low-level classification is typically more concerned with individual components within the system and how they operate.

Due to the nature of complex systems, the high-level description will often be completely different from the low level one. For example, there are features to an ant colony that are not features of any individual ant; features of the human mind that are not known to be descriptive of individual neurons in the brain, features of oceans which are not features of any individual water molecule, and features to a human personality that are not features of any cell in a body. The descriptions of these differ depending at what level they are studied. Features which emerge only at a high level of description are known as epiphenomena.

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