Let's understand what design patterns are and how they will help us to design and develop applications or services.
Design patterns are a way of structuring code to solve commonly-occurring problems in designing software solutions. These are solutions to design problems that are common in the course of software design, unleashing the profundity of experiences to solve common problems of software development. The aim here is to use patterns to solve these problems in a more structured and elegant manner.
Software design or application design tends to change over the time. Any system has to be flexible for any change in the code. A change in the requirements, a new feature request, a defect fix, or a refactoring may require us to restructure the code. When a new piece of code is developed, it has to be gently integrated into the system. Existing code can be...