Email 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.
An email address identifies an email box to which messages are delivered. While early messaging systems used a variety of formats for addressing, today, email addresses follow a set of specific rules originally standardized by the Internet Engineering Task Force (IETF) in the 1980s, and updated by RFC 5322 and 6854. The term email address in this article refers to just the addr-spec in Section 3.4 of RFC 5322. The RFC defines address more broadly as either a mailbox or group. A mailbox value can be either a name-addr, which contains a display-name and addr-spec, or the more common addr-spec alone.
Gmail is the email service provided by Google. As of 2019, it had 1.5 billion active users worldwide, making it the largest email service in the world. It also provides a webmail interface, accessible through a web browser, and is also accessible through the official mobile application. Google also supports the use of third-party email clients via the POP and IMAP protocols.
Yahoo! Mail is an email service offered by the American company Yahoo, Inc. The service is free for personal use, with an optional monthly fee for additional features. Business email was previously available with the Yahoo! Small Business brand, before it transitioned to Verizon Small Business Essentials in early 2022. Launched on October 8, 1997, as of January 2020, Yahoo! Mail has 225 million users.
Email marketing is the act of sending a commercial message, typically to a group of people, using email. In its broadest sense, every email sent to a potential or current customer could be considered email marketing. It involves using email to send advertisements, request business, or solicit sales or donations. The term usually refers to sending email messages with the purpose of enhancing a merchant's relationship with current or previous customers, encouraging customer loyalty and repeat business, acquiring new customers or convincing current customers to purchase something immediately, and sharing third-party ads.
Email authentication, or validation, is a collection of techniques aimed at providing verifiable information about the origin of email messages by validating the domain ownership of any message transfer agents (MTA) who participated in transferring and possibly modifying a message.
Push email is an email system that provides an always-on capability, in which when new email arrives at the mail delivery agent (MDA), it is immediately, actively transferred (pushed) by the MDA to the mail user agent (MUA), also called the email client, so that the end-user can see incoming email immediately. This is in contrast with systems that check for new incoming mail every so often, on a schedule. 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.
ISPConfig is an open source hosting control panel for Linux, licensed under BSD license and developed by the company ISPConfig UG. The ISPConfig project was started in autumn 2005 by Till Brehm from the German company projektfarm GmbH.
Outlook.com, formerly Hotmail, is a free personal email service offered by Microsoft. This includes a webmail interface featuring mail, calendaring, contacts, and tasks services. Outlook can also be accessed via email clients using the IMAP or POP protocols.
United Internet AG is a global Internet services company headquartered in Montabaur, Rhineland-Palatinate, Germany. The company is structured in two business areas, Access and Applications, and has a total of 16 brands and numerous subsidiaries. The well-known brands under the umbrella of United Internet AG include 1&1, IONOS, Fasthosts, GMX, WEB.DE and 1&1 Versatel.
mail.com is a web portal and web-based email service provider owned by the internet company 1&1 Mail & Media Inc., headquartered in Philadelphia, Pennsylvania, United States. 1&1 Mail & Media Inc. is a subsidiary of United Internet Group, a publicly listed internet services company based in Montabaur, Germany.
SMTP Authentication, often abbreviated SMTP AUTH, is an extension of the Simple Mail Transfer Protocol (SMTP) whereby a client may log in using any authentication mechanism supported by the server. It is mainly used by submission servers, where authentication is mandatory.
De-Mail is a German e-government communications service that makes it possible to exchange legal electronic documents between citizens, agencies, and businesses over the Internet. The project was originally called Bürgerportal and has been implemented by the German government in cooperation with private business partners in an effort to reduce the communication costs of public administration and companies.
Fastmail is an email hosting company based in Melbourne, Australia. In addition to its Fastmail-branded services, the company also operates Topicbox, a mailing list service, and Pobox, an email service it acquired in 2015.
Proton Mail is a Swiss end-to-end encrypted email service founded in 2013 and headquartered in Plan-les-Ouates, in the Canton of Geneva of Switzerland. Proton Mail is now run by Proton AG, which also operates Proton VPN, Proton Drive, Proton Calendar, Proton Pass and Proton Wallet. It uses client-side encryption to protect email content and user data before they are sent to Proton Mail servers, unlike other common email providers such as Gmail and Outlook.com.
Mailvelope is free software for end-to-end encryption of email traffic inside of a web browser that integrates itself into existing webmail applications. It can be used to encrypt and sign electronic messages, including attached files, without the use of a separate, native email client using the OpenPGP standard.
Proton AG is a Swiss technology company offering privacy-focused online services. It was founded in 2014 by a group of scientists who met at CERN and created Proton Mail.
