**Preface to "Theory and Application of Fixed Point"**

This book collects the published manuscripts submitted to a Special Issue of Axioms entitled "Theory and Application of Fixed Point".

Fixed point theory is initiated with the famous Banach contraction mapping principle, and has been a subject of considerable and increasing interest. It has applications in many areas of mathematics, science, engineering, economics and even medicine. The pioneering work of Banach and the huge application potential of fixed point theory have inspired numerous researchers to advance the theoretical studies in different directions related to the conditions on the contraction mappings and the relevant spaces. This has resulted in many important achievements in the field.

This book contains some very recent theoretical results related to some new types of contraction mappings defined in various types of spaces. There are also studies related to applications of the theoretical findings to mathematical models of specific problems, and their approximate computations. In this sense, this book will contribute to the area and provide directions for further developments in fixed point theory and its applications.

> **Erdal Karapinar, Juan Mart´ınez-Moreno, Inci M. Erhan** *Editors*
