How to combine multiple parts of a usenet message?

E-mail messages are generally sent to an e-mail server that stores received messages in the recipient's e-mail mailbox. The user later retrieves these messages with either a web browser or an e-mail client that uses one of a number of e-mail retrieval protocols. While some clients and servers preferentially use vendor specific, typically proprietary protocols, most support the Internet standard protocols SMTP for sending e-mail and POP3 and IMAP4 for retrieving e-mail, allowing interoperability with other servers and clients. For example, Microsoft's Outlook client typically uses a proprietary protocol to communicate with an Exchange server as does IBM's Notes client when communicating with a Domino server, but all of these products also support SMTP, POP3, and IMAP4. Support for the Internet standard protocols allows many other e-mail clients such as Qualcomm's Eudora or Mozilla Thunderbird (see comparison of e-mail clients) to access these servers and similarly allows the clients to be used with other servers (see list of mail servers).