In computing, the Internet Message Access Protocol (IMAP) is an Internet standard protocol used by email clients to retrieve email messages from a mail server over a TCP/IP connection. IMAP is defined by RFC 3501.
In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol used by e-mail clients to retrieve e-mail from a mail server.
An email client, email reader or more formally mail user agent (MUA) is a computer program used to access and manage a user's email.
Mutt is a text-based email client for Unix-like systems. It was originally written by Michael Elkins in 1995 and released under the GNU General Public License version 2 or any later version.
Pegasus Mail is a proprietary email client developed by David Harris. It was originally released in 1990 for internal and external mail on NetWare networks with MS-DOS and later Apple Macintosh clients. It was subsequently ported to Microsoft Windows, which is now the only platform actively supported. Previously freeware, Pegasus Mail is now donationware.
Microsoft Entourage is a discontinued e-mail client and personal information manager that was developed by Microsoft for Mac OS 8.5 and later. Microsoft first released Entourage in October 2000 as part of the Microsoft Office 2001 office suite; Office 98, the previous version of Microsoft Office for the classic Mac OS included Outlook Express 5. The last version was Entourage: Mac 2008, part of Microsoft Office 2008 for Mac, released on January 15, 2008. Entourage was replaced by Outlook for Macintosh in Microsoft Office for Mac 2011, released on October 26, 2010.
M+NetMail is an ISP-grade E-mail package by Messaging Architects. It is designed to deliver scalable messaging and calendaring services, using Internet-standard protocols, across a large enterprise, or to a large group of users who are not particularly associated. The original name for the product, when owned by Novell, was Novell Internet Messaging System (NIMS). Messaging Architects showcased NetMail on its MyRealBox website, this service was discontinued on June 1, 2011.
SquirrelMail is a project that provides both a web-based email client and a proxy server for the IMAP protocol.
Kontact is a personal information manager and groupware software suite developed by KDE. It supports calendars, contacts, notes, to-do lists, news, and email. It offers a number of inter-changeable graphical UIs all built on top of a common core.
The following tables compare general and technical features of a number of notable email client programs.
Kolab is a free and open source groupware suite. It consists of the Kolab server and a wide variety of Kolab clients, including KDE PIM-Suite Kontact, Roundcube web frontend, Mozilla Thunderbird and Mozilla Lightning with SyncKolab extension and Microsoft Outlook with proprietary Kolab-Connector PlugIns.
Mercury Mail Transport System is a standards-compliant mail server developed by David Harris, who also develops the Pegasus Mail client.
KDE Software Compilation 4 was the only series of the so-called KDE Software Compilation, first released in January 2008 and the last release being 4.14.3 released in November 2014. It was the follow-up to K Desktop Environment 3. Following KDE SC 4, the compilation was broken up into basic framework libraries, desktop environment and applications, which are termed KDE Frameworks 5, KDE Plasma 5 and KDE Applications, respectively.
The UW IMAP server was the reference server implementation of the IMAP protocol. It was developed at the University of Washington by Mark Crispin and others.
Push email is an email system that provides an always-on capability, in which new email is actively transferred (pushed) as it arrives by the mail delivery agent (MDA) to the mail user agent (MUA), also called the email client. Email clients include smartphones and, less strictly, IMAP personal computer mail applications.
The following tables compare general and technical information for a number of notable webmail providers who offer a web interface in English.
Pocomail was an e-mail client for Microsoft Windows systems that was first developed by Poco Systems in 1999. It was originally designed to provide better spam and attack protection by using its own scripting methods (PocoScript) as opposed to using JavaScript and native Microsoft scripting.
Trojitá is a free software IMAP and SMTP email client developed using the Qt C++ library. The design goals of the maintainers are to develop a fast e-mail client which respects open standards, is cross-platform and uses the available resources very efficiently.
GyazMail is an email client for macOS, developed and being maintained by the Japanese programmer Goichi Hirakawa. It supports the POP3, IMAP and SMTP protocols. Its handling of multiple email accounts includes local mailboxes.
