Email client

An email client (alternatively spelled e-mail client; commonly known as mail client; more formally known as mail user agent or MUA; hereinafter, the Client) is any digital construct that an end-user utilizes to compose, access, and/or manage his or her emails.

The Client can also refer to mail client software. More broadly, email software may refer to all the software utilized for the Clients, mail servers, or mail exchangers.

Functions

Communication

With regard to:

• Outgoing messages, the Clients may be designed to:
  1. Accept requests from end-users to compose new messages.
  2. Analyze requests looking for their inconsistencies and/or missing data.
  3. Offer end-users to correct inconsistencies and/or add the missing data.
  4. Transfer messages to mail servers.
• Stored messages, the Clients may be designed to:
  1. Accept requests from end-users to manage -- delete, arrange, label, classify -- stored messages.
  2. Offer end-users to confirm those changes that are setup as critical.
  3. Execute the requests -- delete, arrange, label, classify -- stored messages.
• Incoming messages, the Clients may be designed to:
  1. Accept messages from mail servers.
  2. Analyze messages looking for their inconsistencies and/or missing data.
  3. Add information about the found inconsistencies and/or missing data to the messages. This information may further be used by mail clients to combat spam.
  4. Display messages to end-users.

On the one side, the Clients receive requests from and display the data to end-users. On the other side, the Clients communicate with mail servers in order to receive emails from and/or send emails to.

Hosting

There are two major models of locating the Clients:

1. On-premises: end-users may install the Clients on their devices; a common example would be an app running on one's cell phone. The POP3 protocol is commonly used for sending one's emails to and/or receiving from mail servers.
2. Online: end-users may access the Clients that are hosted online, often, next to a mail server. The IMAP protocol is commonly used for accessing and/or managing one's emails online.

Software

Comparison of popular Clients

Features	Evolution	Outlook	RoundCube	Thunderbird	Zimbra

Related lectures

• Communication Quarter.