Comparison of email clientsThe following tables compare general and technical features of notable email client programs. Basic general information about the clients: creator/company, O/S, licence, & interface. Clients listed on a light purple background are no longer in active development. A brief digest of the release histories. The operating systems on which the clients can run natively (without emulation). What email and related protocols and standards are supported by each client. Information on what features each of the clients support.
End-to-end encryptionEnd-to-end encryption (E2EE) is a private communication system in which only communicating users can participate. As such, no one, including the communication system provider, telecom providers, Internet providers or malicious actors, can access the cryptographic keys needed to converse. End-to-end encryption is intended to prevent data being read or secretly modified, other than by the true sender and recipient(s). The messages are encrypted by the sender but the third party does not have a means to decrypt them, and stores them encrypted.
Email filteringEmail filtering is the processing of email to organize it according to specified criteria. The term can apply to the intervention of human intelligence, but most often refers to the automatic processing of messages at an SMTP server, possibly applying anti-spam techniques. Filtering can be applied to incoming emails as well as to outgoing ones. Depending on the calling environment, email filtering software can reject an item at the initial SMTP connection stage or pass it through unchanged for delivery to the user's mailbox.
Mailing listA mailing list is a collection of names and addresses used by an individual or an organization to send material to multiple recipients. The term is often extended to include the people subscribed to such a list, so the group of subscribers is referred to as "the mailing list", or simply "the list." Transmission may be paper-based or electronic. Each has its strengths, although a 2022 article claimed that "direct mail still brings in the lion's share of revenue for most organizations.
Email attachmentAn email attachment is a sent along with an email message. One or more files can be attached to any email message, and be sent along with it to the recipient. This is typically used as a simple method to share documents and images. Originally, ARPANET, UUCP, and Internet SMTP email allowed 7-bit ASCII text only. Text files were emailed by including them in the message body. In the mid 1980s text files could be grouped with UNIX tools such as bundle and shar (shell archive) and included in email message bodies, allowing them to be unpacked on remote UNIX systems with a single shell command.
Message transfer agentWithin the Internet email system, a message transfer agent (MTA), or mail transfer agent, or mail relay is software that transfers electronic mail messages from one computer to another using the Simple Mail Transfer Protocol. In some contexts the alternative names mail server, mail exchanger, and MX host can be used to describe an MTA. Messages exchanged across networks are passed between mail servers, including any attached data files (such as images, multimedia or documents). These servers also often keep mailboxes for email.
News aggregatorIn computing, a news aggregator, also termed a feed aggregator, feed reader, news reader, RSS reader, or simply an aggregator is client software or a web application that aggregates syndicated web content such as online newspapers, blogs, podcasts, and video blogs (vlogs) in one location for easy viewing. The updates distributed may include journal tables of contents, podcasts, videos, and news items. Visiting many separate websites frequently to find out if the content on the site has been updated can take a long time.
Email encryptionEmail encryption is encryption of email messages to protect the content from being read by entities other than the intended recipients. Email encryption may also include authentication. Email is prone to the disclosure of information. Most emails are encrypted during transmission, but they are stored in clear text, making them readable by third parties such as email providers. By default, popular email services such as Gmail and Outlook do not enable end-to-end encryption.
Email spoofingEmail spoofing is the creation of email messages with a forged sender address. The term applies to email purporting to be from an address which is not actually the sender's; mail sent in reply to that address may bounce or be delivered to an unrelated party whose identity has been faked. Disposable email address or "masked" email is a different topic, providing a masked email address that is not the user's normal address, which is not disclosed (for example, so that it cannot be harvested), but forwards mail sent to it to the user's real address.
