In an interface, we can define a property and later implement it. However, the issue I recently encountered is that if we define a ‘list’ or ‘array’, we must ultimately implement the properties as private.

In contrast, for int or string, we do not have this problem and can write them as public.

Why?!

for exm :

 interface IEmployee
{
    string Name{get; set;}
    List<string> Friends
}

public class Employee : IEmployee
{
  .
  .
  .
  public Name{get;set;} // Must be public *****
   List<string> IEmployee.Friends { get ; set ; } // Must Be Private through IEmployee *****
  .
  .
  .
}