# Low Level Design
All Low Level Design notes →1 — Identifying Entities
Covers how to identify entities in a domain model — objects with a persistent identity that spans changes to their attributes over time.
2 — Value Objects
Revisits value objects in the context of domain modeling, where they capture descriptive attributes of an entity without carrying identity of their own.
3 — Aggregates
Explains aggregates as consistency boundaries that group entities and value objects behind a single root for transactional integrity.
4 — Domain Services
Covers domain services for modeling operations that don't naturally belong to any single entity or value object in the model.
5 — Repositories
Introduces the repository pattern for abstracting aggregate persistence and retrieval behind a collection-like interface.
6 — Domain Events
Explains domain events as a way to capture and propagate significant state changes within a domain model to other parts of a system.