What is a navigation property?

Short answer: Navigation properties allow navigation from one entity to related entities. They define relationships (one-to-one, one-to-many, many-to-many). Example: public class Order

Example code

{
public int Id { get; set; }
public Customer Customer { get; set; } // Navigation property
}

Real-world example (ShopNest)

ShopNest’s order service uses EF Core to save an Order and its line items in one SaveChangesAsync() call inside a transaction.

Say this in the interview

1. Define — one clear sentence (the short answer above).
2. Example — relate it to a project like ShopNest or your real work.
3. Trade-off — when you would not use it.