 
 <prompt> Wetin 'S' mean for SMTP? Based on di last question, write one context wey contain di answer. E fit be 1 - 20 sentences. Context: <response>: ```Plenti mailbox providers na also access providers, while some no be (e.g., Yahoo! Mail, Outlook.com, Gmail, AOL Mail, Po box). The definition wey dey for RFC 6650 cover email hosting services, as well as the relevant department of companies, universities, organizations, groups, and individuals wey dey manage their mail servers themselves. The work dey usually done by implementing Simple Mail Transfer Protocol (SMTP) and possibly providing access to messages through Internet Message Access Protocol (IMAP), the Post Office Protocol, Webmail, or a proprietary protocol.``` 