Uncertain systems is a class of systems characterized by parameters, states, or dynamics that are not precisely known or are subject to inherent variability. This academic concept constitutes a research field focused on developing theoretical frameworks and methodologies for the analysis, modeling, control, and prediction of systems where complete and precise information is unavailable. Key characteristics involve the presence of irreducible uncertainty, which may be represented stochastically, epistemically, or through alternative formalisms such as intervals or fuzzy sets; its significance lies in enabling robust design, reliable performance assessment, and informed decision-making across diverse scientific and engineering disciplines.