This book presents current research on Ulam stability for functional equations and inequalities. Contributions from renowned scientists emphasize fundamental and new results, methods and techniques. Detailed examples are given to theories to further understanding at the graduate level for students in mathematics, physics, and engineering.

Key topics covered in this book include:

• Quasi means
• Approximate isometries
• Functional equations in hypergroups
• Stability of functional equations
• Fischer-Muszély equation
• Haar meager sets and Haar null sets
• Dynamical systems
• Functional equations in probability theory
• Stochastic convex ordering
• Dhombres functional equation
• Nonstandard analysis and Ulam stability