In software development, we often need to traverse elements in data structures, such as collections, arrays, or linked lists. In order to avoid coupling the traversal logic inside the data structure and improve the readability and scalability of the code, the Iterator Pattern came into being. This article will introduce in detail the concept of the Iterator Pattern, the difference from other patterns, the problems it solves, and how to implement and use the Iterator Pattern in Golang. What is the Iterator Pattern?