Level of abstraction

In computer science, an abstraction level (or abstraction layer ) is a generalization of a model or algorithm, away from any specific implementation. These generalizations arise from broad similarities that are best encapsulated by models that express similarities present in various specific implementations. The simplification provided by a good abstraction layer allows for easy reuse by distilling a useful concept or metaphor so that situations where it may be accurately applied can be quickly recognized.

A good abstraction will generalize that which can be made abstract; while allowing specificity where the abstraction breaks down and its successful application requires customization to each unique requirement or problem.

Frequently abstraction layers can be composed into a hierarchy of abstraction levels or abstraction layers . The OSI ISO networking model is comprised of seven abstraction layers. Each layer of the OSI ISO networking model encapsulates and addresses a different part of the needs of much digital communications thereby reducing the complexity of the associated engineering solutions.

A famous aphorism of Butler Lampson goes: All problems in computer science can be solved by another level of indirection; this is often deliberately mis-quoted with "abstraction" substituted for "indirection".