What is difference between DTO and POCO classes in VS

POCO- Plain Old CLR (or) Class Object

public class Employee
{
    public int Id {get;set;}
    public string FirstName{get;set;}
    public void Salary()
    { 
        Console.WriteLine("10000");
    }
}
DTO -no behaviour - Data Transfer Object

public class EmployeeDTO
{
    public int Id {get;set;}
    public string FirstName {get;set;}
}