Difference between ECC 5 and NetWeaver 2004s

Dear friends

please tell me what is the difference between ECC 5 and NetWeaver... as we can have EP, XI, WAS, CRM, SRM this things with NetWeaver and same as ECC also.. so what is the difference....i am confused please please...help me to clear my doubt on ECC and NetWeaver

thanking you

regards

NAim