Stability

The word stability has a number of technical meanings, all related to the common meaning of the word.

In mechanical systems, stability characterizes the result of small perturbations to a system in mechanical equilibrium.
- A special case of mechanical stability is plasma stability.
- In Meteorology stability in the air relates to vertical movements of air parcels.
- On a boat it refers to the righting moment, and the resistance of the boat to capsize.
In system analysis, control theory, and signal processing, stability characterizes the reaction of a dynamic system to external influences.
- BIBO (Bounded Input, Bounded Output) stability
- Lyapunov stability
- stability of a polynomial
The concept is also used in "softer" sciences:
- In chemistry, stablility can refer to a chemical isotope in a stable form.
- In ecology, ecological stability can take on any connotaion in a continuum ranging from returning quickly to a previous state to simply not going extinct.
- In sociology, stability refers to social stability.
In computer science and mathematics, the term has additional meanings.
- In numerical analysis, stability refers to how well an algorithm performs with regard to error in the numerical results: see numerical stability.
- In probability, stability is an important property of certain probability distributions. (See stability (probability).)
- In everyday conversation about computers, stability is the tendency or otherwise of a system or program to crash.