What is Domain-Driven Design (DDD) in a nutshell? How does it relate to OOP?

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Domain-Driven Design is an approach to software design that puts the business domain and its language at the center of the architecture. DDD encourages close collaboration with domain experts, explicit domain models, bounded contexts, entities, value objects, aggregates, domain services, domain events, and ubiquitous language. OOP provides many of the implementation mechanisms used to represent these concepts, but DDD is broader than OOP. public sealed class Money
{
 public decimal Amount { get; }
 public string Currency { get; }

public Money(decimal amount, string currency)
 {
 if (amount < 0)
 throw new ArgumentException("Amount cannot be negative");

Amount = amount;
 Currency = currency;
 }
}

public class Order
{
 private readonly List lines = new();

public void AddLine(Product product, int quantity)
 {
 if (quantity <= 0)
 throw new ArgumentException("Quantity must be positive");

lines.Add(new OrderLine(product, quantity));
 }
} Entities have identity and usually represent concepts with a lifecycle. value Objects are defined by their values rather than identity. Aggregates define transactional consistency boundaries. Bounded Contexts separate models whose meanings or rules differ. Ubiquitous Language creates a shared vocabulary between developers and domain experts. Domain events represent meaningful business occurrences. OOP supports encapsulation, polymorphism, composition, and domain behavior, while DDD provides strategic and tactical modeling guidance. DDD should be applied where domain complexity justifies it; it can be unnecessary overhead for simple applications.

What is Domain-Driven Design (DDD) in a nutshell? How does it relate to OOP?

DDD and Object-Oriented Design

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