There are over 2500 RFC's. Each RFC is known by a number. For instance, RFC 1180 presents a tutorial on TCP/IP, RFC 1920 lists the current standards RFC's and explains the RFC standards process, and RFC 1941 is a FAQ list on the topic of Internet deployment in educational establishments.
MX record. A mail exchanger record (MX record) is a type of resource record in the Domain Name System that specifies a mail server responsible for accepting email messages on behalf of a recipient's domain, and a preference value used to prioritize mail delivery if multiple mail servers are available.
Microsoft XPS Document Writer (MXDW) The Microsoft XPS Document Writer (MXDW) is a print-to-file driver that enables a Windows application to create XML Paper Specification (XPS) document files on versions of Windows starting with Windows XP with Service Pack 2 (SP2).