Electronic mail is a method of transmitting and receiving messages using electronic devices. It was conceived in the late–20th century as the digital version of, or counterpart to, mail. Email is a ubiquitous and very widely used communication medium; in current use, an email address is often treated as a basic and necessary part of many processes in business, commerce, government, education, entertainment, and other spheres of daily life in most countries.
An email client, email reader or, more formally, message user agent (MUA) or mail user agent is a computer program used to access and manage a user's email.
HCL Notes and HCL Domino are the client and server, respectively, of a collaborative client-server software platform formerly sold by IBM, now by HCL Technologies.
GNOME Evolution is the official personal information manager for GNOME. It has been an official part of GNOME since Evolution 2.0 was included with the GNOME 2.8 release in September 2004. It combines e-mail, address book, calendar, task list and note-taking features. Its user interface and functionality is similar to Microsoft Outlook. Evolution is free software licensed under the terms of the GNU Lesser General Public License (LGPL).
Microsoft Outlook is a personal information manager software system from Microsoft, available as a part of the Microsoft Office and Microsoft 365 software suites. Though primarily being popular as an email client for businesses, Outlook also includes functions such as calendaring, task managing, contact managing, note-taking, journal logging and web browsing.
Outlook Express, formerly known as Microsoft Internet Mail and News, is a discontinued email and news client included with Internet Explorer versions 3.0 through 6.0. As such, it was bundled with several versions of Microsoft Windows, from Windows 98 to Windows Server 2003, and was available for Windows 3.x, Windows NT 3.51, Windows 95, Mac System 7, Mac OS 8, and Mac OS 9. In Windows Vista, Outlook Express was superseded by Windows Mail.
Sylpheed is an open-source e-mail client and news client licensed under GNU GPL-2.0-or-later with the library part LibSylph under GNU LGPL-2.1-or-later. It provides easy configuration and an abundance of features. It stores mail in the MH Message Handling System. Sylpheed runs on Unix-like systems such as Linux or BSD, and it is also usable on Windows. It uses GTK+.
Mozilla Thunderbird is a free and open-source cross-platform email client, personal information manager, news client, RSS and chat client that is operated by the Mozilla Foundation's subsidiary MZLA Technologies Corporation. Thunderbird is an independent, community-driven project that is managed and overseen by the Thunderbird Council, which is elected by the Thunderbird Community. The project strategy was originally modeled after that of Mozilla's Firefox web browser and is an interface built on top of that web browser.
Bogofilter is a mail filter that classifies e-mail as spam or ham (non-spam) by a statistical analysis of the message's header and content (body). The program is able to learn from the user's classifications and corrections. It was originally written by Eric S. Raymond after he read Paul Graham's article "A Plan for Spam" and is now maintained together with a group of contributors by David Relson, Matthias Andree and Greg Louis.
Apple Mail is an email client included by Apple Inc. with its operating systems macOS, iOS, iPadOS and watchOS. Apple Mail grew out of NeXTMail, which was originally developed by NeXT as part of its NeXTSTEP operating system, after Apple's acquisition of NeXT in 1997.
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.
The Bat! is an email client for the Microsoft Windows operating system, developed by Ritlabs, SRL, a company based in Chişinău, Moldova. There are two versions: a Home version and a Professional version. The Professional version includes a portable module, The Bat Voyager.
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.
Opera Mail is the email and news client developed by Opera Software. It was an integrated component within the Opera web browser from version 2 through 12. With the release of Opera 15 in 2013, Opera Mail became a separate product and is no longer bundled with Opera. Opera Mail version 1.0 is available for OS X and Windows. It features rich text support and inline spell checking, spam filtering, a contact manager, and supports POP3 and IMAP, newsgroups, and Atom and RSS feeds.
The MH Message Handling System is a free, open source e-mail client. It is different from almost all other mail reading systems in that, instead of a single program, it is made from several different programs which are designed to work from the command line provided by the shell on Unix-like operating systems. Another difference is that rather than storing multiple messages in a single file, messages each have their own separate file in a special directory. Taken together, these design choices mean that it is very easy and natural to script actions on mail messages using the normal shell scripting tools.
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 notable email client programs.
Windows Live Mail was a freeware email client from Microsoft. It is the successor to Windows Mail in Windows Vista, which was the successor to Outlook Express in Windows XP and Windows 98. Windows Live Mail is designed to run on Windows 7 and Windows Server 2008 R2, but is also compatible with Windows 8 and Windows 10, even though Microsoft bundles a new email client, named Windows Mail, with the latter.
Mail is an email client developed by Microsoft and included in Windows Vista and later versions of Windows. It is available as the successor to Outlook Express, which was either included with, or released for Internet Explorer 3.0 and later versions of Internet Explorer.
