Remote Access Services (RAS) is the Windows service that handles dial-up networking connections via modem. RAS is installed by default on most Win9x machines. On NT machines, however, RAS is not installed until you add a modem device to the system configuration. On Windows 9x, dialup-networking automatically starts when an application attempts to connect to a remote machine. Under Windows NT, however, this does not occur and it's up to the user to explicitly dial with RAS.
SAPI is something to do with Microsoft? speech I believe.