# Glossary

## A

Account

  An account represents an identity within Claws Mail. As such only one email address is associated with each account. However, the number of accounts you can setup is unlimited.

Action (filtering/processing rules)

  An action is something that is performed on a message when it matches the rule conditions. A typical action is moving the message to a particular folder. See also .

Actions

  Actions are user-defined commands that can be applied to a message, or part of a message, using a special syntax. They are presented to the user in a customisable menu.

Address book

  Storage for names, mail addresses and custom user attributes. Also provides access to servers and files.

ASCII

  American Standard Code for Information Interchange. A standard using 7 bit. It's defined as an Internet standard in RFC 20.

Attachment

  Additional file(s) included with a mail message. Some attachments can be displayed by Claws Mail, others require external programs. can provide additional functions for attachments.

## C

Character encoding

  A map between written symbols, like letters and other symbols, and the numbers used to represent them inside the computer. The most well-known character encoding is probably , but it has been superseded by others, such as .

Compose

  Create new a message text or a reply to a received mail in the Compose window.

Condition (filtering/processing rules)

  The prerequisites that a mail message must fulfil in order for the rule's action to be executed. See also .

## D

Digital signature (GPG)

  A piece of data obtained from merging a message and a cryptographic key which ensures message authorship, in a similar way that a hand-written signature does in a document. This piece of data is sent with the m essage so the recipient can verify its validity.

## E

Encryption (GPG)

  Scrambling a message with a cryptographic key so that only the recipient and ownwer of the key password can unscramble it for reading.

## F

Face

  A more modern implementation of the , it's a coloured image (48x48 pixels) included in the message headers.

Filtering rule

  A applied to incoming messages. Filtering rules can be also applied manually to the contents of any folder.

Folder

  A folder is the primary message container. Folders can be local or remote, but they are managed in a uniform way by Claws Mail.

Forward

  To send a copy of a received mail to another recipient, optionally adding your own message.

## H

Headers

  Machine readable lines which form the first part of a mail message. The purpose of headers varies; Typical headers are From and To which state the sender and recipient of the message, others are used by the mail system. Some headers are optional and are used to provide additional information, such as or .

HTML

  Acronym for Hyper-Text Markup Language. It was the standard language to encode web pages in the beginning of the . Some mail clients use this language to encode the textual body of mails in order to craft special effects to text at the cost of multiplying the message size several times. HTML mail is also widely used by spammers to send .

## I

IMAP4

  Internet Messaging Access Protocol (version 4). A protocol for accessing email on a remote server from a local client. All messages are stored in the remote server.

Immediate execution

  When the Execute immediately when moving or deleting messages option is used, operations performed on messages, (like deletions or movements), are performed immediately. If the option is turned off, all operations performed on messages by the user are only carried out when the Execute button is pressed.

ISP

  Internet Service Provider. A company which provides Internet access to its customers. In the dialup access age these were the big telephony companies, with the arrival of broadband access the number of companies and types of services offered has grown exponentially.

## L

LDAP

  Lightweight Directory Access Protocol. A protocol for accessing information directories such as organisations, individuals, phone numbers, and addresses.

LDIF

  LDAP Data Interchange Format. A text file format widely used for moving data between servers and/or other programs.

Local mbox file

  A local mailbox spool file in format.

Log window

  A special window which records protocol operations in detail that are performed by Claws Mail. It's a useful tool for debugging.

## M

Mailbox

  The root folder of the folder hierarchy.

Maildir

  A mailbox format in which all mail is kept in separate files. Maildir++ is an extension to the maildir format.

Mailing-List

  Electronic mailing-lists are a special usage of email that allows for widespread distribution of information to many Internet users. They often take the form of discussion lists, like the Claws Mail users' list, where a subscriber uses the mailing-list to send messages to all the other subscribers, who may answer in similar fashion.

Mark (message)

  A tag that can be set on a message by the user in order to draw attention to the message. Marks are shown in the Mark column of the Message List.

MBox

  A mailbox format in which all mail is concatenated and stored in a single file. The mbox format supported by Claws Mail is `mboxrd`.

Message

  A message is the basic piece of information handled by Claws Mail. A message is usually an email message, which is stored in format on disk. Other kinds of messages (and storage formats) can be handled through .

MH

  A mailbox format in which all mail is kept in separate files. This is the default mailbox format used by Claws Mail.

MIME

  Multipurpose Internet Mail Extensions. Internet standards for representing binary data in text format, encoding and s.

## N

NNTP

  Network News Transfer Protocol. The protocol used to post, distribute, and retrieve messages, also called news articles or simply news for short.

Newsgroups

  A set of hierarchical partitions of messages on a . The protocol allows the user to subscribe to one or more newsgroups. New messages posted to the subscribed groups are automatically downloaded on connection.

News server

  Server which provides access to messages in through the protocol.

## P

PDF

  Portable Document Format. An open binary file format developed by Adobe Systems to allow interchanging of printable documents between different platforms. Inherits some features from but not being a language made it easier to process, especially on desktop computers.

PGP Inline

  Digital signing method which includes the signature data in the message body. Currently deprecated in favour of .

PGP MIME

  Digital signing method which includes the signature data as a separate .

Plugins

  External modules which can be loaded and used by Claws Mail to extend its functionality. Technically speaking these modules are shared libraries which can register one or several functions to be called by Claws Mail when something interesting is being done.

POP3

  Post Office Protocol (version 3). A protocol for retrieving email from a remote server. Messages can be automatically removed from server after downloading.

PostScript

  Page description language primarily used and understood by printing devices to generate its output. Was developed by Adobe Systems and is now a widely used standard in the printing industry. As it's a fully featured interpreted language it requires some processing power to deal with.

Privacy (GPG)

  Privacy provides methods for both signing and encrypting mail messages you send and also for verifying and decrypting signed and encrypted messages that you receive.

Processing rule

  A or set of rules belonging to a folder which are executed on entering the folder.

## Q

Queue

  Temporary storage for messages which are waiting to be sent, either because they couldn't be sent due a network failure or because the user requested them to be sent later.

Quick Search

  A powerful way to search for messages using almost any criteria that you can think of.

Quotation

  When replying to a message the user will often include a quoted section of that message to provide the context. The quoted section is shown by the prepending of a common character, usually >.

## R

Recursive (Quick Search)

  A recursive will also search in all subfolders of the selected folder.

Redirect

  To send a copy of a received mail in its original form to another recipient.

Reply

  Answer to a received message. As verb also the act of answering a message.

ROT-13

  Simple encryption method used since Romans age, which uses an alphabet rotated thirteen positions to encode each letter of the message. Used sometimes to hide funny messages on mails.

Rule

  Logical structure comprised of one or more conditions (see ) and one or more associated actions (see ). Rules are used for filtering mail messages.

## S

SMTP

  Simple Mail Transfer Protocol. A protocol for sending email to servers.

SMTP server

  A server which receives mail messages from other hosts and/or sends mail messages to other hosts using the protocol.

Source (message)

  The full text of a message as it is transmitted over the network. This includes all headers, message body and encoded attachments if present.

Spam

  Junk mail, unsolicited commercial emails.

Spell checking

  Automatic verification of spelling while typing or after composition has finished.

SSL

  Secure Sockets Layer. A protocol used to encrypt and protect data sent over a network.

SSL certificate

  A certificate installed on a secure server that is used for identification.

STARTTLS

  STARTTLS (Start Transport Layer Security) is a command used to initiate a secure connection between two servers using .

Sticky (Quick Search)

  When the sticky option is set on the search terms are not cleared when changing folders.

Synchronisation (folder)

  Making the contents of a local folder mirror those of an equivalent remote folder in the associated mail server.

## T

TCP

  Transmission Control Protocol. The main protocol used in the Internet. Allows media-independent reliable connections between two endpoints and is supported by all modern Operating Systems in use.

Themes

  Image sets for changing the appearance of buttons, folders and other graphical elements of Claws Mail.

Thread (messages)

  A set of messages loosely relating to each other.

Toolbars

  Sets of buttons arranged horizontally which provide access to all commonly used functions. Toolbars in Claws Mail can be customised.

## U

UIDL

  Unique IDentification Listing. A command which allows single message handling by asigning a unique identifier for each message.

URL

  Uniform Resource Locator. A naming scheme for objects (usually files) in a multi-protocol networked environment like current Internet. For example, this is the one of the Claws Mail home page: `http://www.claws-mail.org`.

USENET

  User's Network. A bulletin board system of discussion groups, often called .

UTF-8

  8-bit Unicode Transformation Format. A variable length character encoding capable of representing any universal character. An Internet standard defined in RFC 3629.

## V

vCard

  File format standard for Personal Data Interchange, it can hold information such as address, phone numbers, etc., much like the information usually found in a business card. They are commonly found attached to mail messages.

## W

Wrapping

  Restructuring of the message text based on a user-defined maximum number of characters per line. Wrapping ensures that paragraphs are justified, which means that they are aligned to the left and right margins.

WWW

  World Wide Web, the hyperlinked network of web pages across the Internet.

## X

X-Face

  Specially coded black and white image (48x48 pixels) included in the message headers. Capable mailers like Claws Mail and others can decode and show it alongside the message text. Although they are not unique, they can help to quickly identify the message sender. See also .