mobile web apps

  This is a   list of mail server software :   mail transfer agents ,   mail delivery agents , and other   computer software   which provide   e-mail . Contents 1 Product statistics 2 SMTP 3 POP/IMAP 4 Mail filtering 5 Mail server packages 6 See also 7 References Product statistics [ edit ] All such figures are necessarily estimates because data about mail server share is difficult to obtain; there are few reliable primary sources—and no agreed methodologies for its collection. Surveys probing Internet-exposed systems typically attempt to identify systems via their banner, or other identifying features; [1]  and report  Postfix  and  exim  as overwhelming leaders in March 2021, with greater than 92% share between them. [1] SMTP [ edit ] agorum core Apache James Axigen Citadel CommuniGate Pro Courier Eudora Internet Mail Server Exim FirstClass Gordano Messaging Suite Halon Haraka hMailServer IBM   Lotus Domino IceWarp Mail ...

  The   Simple Mail Transfer Protocol   ( SMTP ) is an   internet standard   communication protocol   for   electronic mail   transmission. Mail servers and other   message transfer agents   use SMTP to send and receive mail messages. User-level   email clients   typically use SMTP only for sending messages to a mail server for relaying, and typically submit outgoing email to the mail server on port 587 or 465 per   RFC   8314 . For retrieving messages,   IMAP   (which replaced the older   POP3 ) is standard, but proprietary servers also often implement proprietary protocols, e.g.,   Exchange ActiveSync . Since SMTP's introduction in 1981, it has been updated, modified and extended multiple times. The protocol version in common use today has extensible structure with various extensions for  authentication ,  encryption , binary data transfer, and  internationalized email addresses . ...