juniorDDD

What is an Entity in DDD?

Updated Apr 28, 2026

Short answer

An Entity is an object defined primarily by its identity rather than its attributes. It has a lifecycle and remains the same object even if its properties change.

Deep explanation

DDD is not just about coding; it's about modeling the business. By using Ubiquitous Language, we ensure the code reflects the mental model of the domain experts. Entities handle identity (like a User ID), while Value Objects handle data (like an Address).

Real-world example

An e-commerce system where 'Order' is an Entity, but 'Shipping Address' is a Value Object.

Common mistakes

  • Making everything an Entity even if it doesn't need identity.

Follow-up questions

  • Why are Value Objects immutable?

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