Oracle Connection String - What exactly the difference?

.Net Framework Connection string: "Provider=MSDAORA;Data Source= Your_Oracle_Database; UserId=Your_Username; Password=Your_Password;"

Connection string to obviate the need - tnsnames.ora

string oradb = "Data Source=(DESCRIPTION=" + "(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=ORASRVR)(PORT=1521)))" + "(CONNECT_DATA=(SERVER=DEDICATED)(SERVICE_NAME=ORCL)));" + "User Id=scott;Password=tiger;";