In signal processing, specifically control theory, bounded-input, bounded-output (BIBO) stability is a form of stability for signals and systems that take inputs. If a system is BIBO stable, then the output will be bounded for every input to the system that is bounded.
A signal is bounded if there is a finite value B > 0 {\displaystyle B>0} such that the signal magnitude never exceeds B {\displaystyle B} , that is