Understanding Generic Collections in C#

//order by SeviceDate desc, ProcedureCode asc 

claimList.Sort(delegate(Claim x, Claim y)

{

     int resultDate = 0 - x.ServiceDate.CompareTo(y.serviceDate);

     int resultCode = x.ProcedureCode.CompareTo(y.ProcedureCode);

     return resultDate + resultCode;

}