For the specific object-oriented programming challenge, design patterns suggest a specific implementation. If you want to ensure that there is only one instance of a class, for example, you could build it using the Singleton design pattern such that it can only hold one object. By offering syntactic characteristics and semantic support for concepts that correspond to those found in object-oriented design, programming language C# promotes the development of object-oriented software. In this course, 23 design patterns are discussed.