Check out example codes for "asp.net mvc 5 codefirst dropdown list". It will help you in understanding the concepts better.

Code Example 1

public class Product
 {
    public int Id { get; set; }
    public string Name { get; set; }      
    public string Description { get; set; }

    public int CategoryId { get; set; }
    public Category Category { get; set; }
 }

 public class Category
 {
    public int Id { get; set; }
    public string Name { get; set; }
    public string Description { get; set; }

    public virtual ICollection<Product> Products { get; set; }
 }

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