Domain-Driven Design (DDD) is a software development approach that focuses on designing software around the business domain, which refers to the core subject matter and activities of an organization. The primary goal of DDD is to ensure that the software system reflects the complexities and nuances of the business domain it serves. It encourages developers, domain experts, and stakeholders to collaborate closely to build a shared understanding of the domain and its terminology, known as the ubiquitous language.

DDD divides the domain into subdomains and represents each with a specific model, ensuring that the software mirrors the real-world business rules and workflows. These models are encapsulated within bounded contexts, which are isolated from other parts of the system, helping to manage complexity and avoid coupling.

DDD is especially valuable for large, complex systems where the business logic is critical to success. It promotes best practices like event-driven architectures, aggregates, and value objects, which help to design maintainable and scalable software systems.

By focusing on domain knowledge and its correct representation in the software, DDD bridges the gap between technical and non-technical team members, enabling the development of systems that better align with business goals.