In Entity Framework, POCO entities (Plain Old CLR Objects) are classes that represent persistent entities without any dependency on the Entity Framework or any specific framework-related base classes. POCO entities are simple, plain C# or VB.NET classes that do not contain any code or attributes specific to the ORM framework.

POCO entities are often used in Entity Framework to provide a clean and decoupled approach to defining the domain model. They can be created with standard language constructs and can be easily understood and maintained without any framework-specific knowledge.

Here's an example of a POCO entity representing a "Customer" in Entity Framework:

public class Customer
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string Email { get; set; }
    public DateTime BirthDate { get; set; }
}

In this example, the Customer class is a POCO entity that represents a customer with properties like Id, Name, Email, and BirthDate. It doesn't include any attributes or base classes specific to Entity Framework.

POCO entities allow for a more flexible and testable approach since they are not tightly coupled to any specific framework. They can be used in various scenarios, including unit testing, dependency injection, and domain-driven design.

When using POCO entities in Entity Framework, the mappings between the entity properties and the database tables can be defined using conventions or through fluent API configuration. This allows Entity Framework to understand how the POCO entities relate to the database schema and perform CRUD operations accordingly.