An online record of all the information about a user: which groups they belong to, their password or social login method, and preferences and settings that apply to all their groups. An account is identified by an email address.


An alternate name for a group or for a hashtag in a group, or an alternate email address associated with a member’s account (for posting purposes only). Refer to this table for more information:

For this type of alias:


Group Owners Manual > Creating group aliases

Note: The group alias feature is available only in Premium and Enterprise groups.

Hashtag Owners Manual > Managing hashtags > Viewing, creating, modifying, and deleting hashtags (scroll to Creating a hashtag and review the “Alias” entry in the table in step 3)

Email Members Manual > Understanding accounts > Setting account preferences and viewing account information (scroll to Setting or changing account login elements and review the “Add email aliases” entry in the table)


A repository of all messages posted to a group, except messages that have been deleted. The messages in the archive are displayed in chronological order on a group’s website when someone clicks the Messages link.

Bounce, bouncing

An event that occurs when an email message cannot be delivered to a member due to a reason such as an incorrect email address, a full mailbox, or a problem connecting to an email server. The system also bounces messages containing new hashtags in a group in which the owner has specified the Hashtag Permissions setting, “Messages from members can only be tagged with existing hashtags, otherwise the message is bounced.”

Standard text that is included at the bottom of every email message sent by Most of the footer text is system generated, but group owners can include custom text through a group setting as well as for individual hashtags.

For more information, see Understanding message footers in the Members Manual

Note: Footers are not displayed in messages in the archive on a group’s website.


A word, or a phrase with no spaces (hyphens and underscores are allowed), prefixed with the hash/pound/number/octothorpe character (#). A group member applies a hashtag to a message by including the hashtag within or at the end of the message’s subject line. A maximum of five hashtags can be applied per topic.


A connection from a group to another service such as GitHub.


A person whose email address is registered with (has a account).

Note: In the past, the term subscriber was often used interchangeably with member. However, member is the preferred term.

Member badges

See Member badges and topic icons.

Member directory

An index of the profiles of group members who opt to share their profile with the group. Owners can specify whether a group’s directory is visible to all members or only to owners and moderators, or whether the directory feature is enabled at all.

Member list

A list of all of the members in a group along with their display names, email addresses, message delivery options, join dates, and bounce status. The list also includes any members who have been banned. Owners can specify whether a group’s member list is visible to all members (which requires the group to have restricted membership) or only to owners and moderators.


A member of a group who has permission to perform certain actions to help run the group, such as approving messages or membership requests, editing messages in the archive, and so on. A group can have more than one moderator, and individual moderators can have different sets of permissions.


A moderator of a group who has all possible permissions and, therefore, has complete control over the group. A group can have more than one owner. Someone who creates a group is an owner automatically.


Personal information provided by members that they can choose to include in the directories of groups to which they belong. Members have a account profile as well as a separate profile for each group, and they can customize their profile for each group they belong to.

Profiles are listed in the Identity section of a member’s account page.

Push notification

See Web/app notification.

Special notice

A message that is sent as an individual email message to all group members regardless of their email delivery setting.

Exception: Members who set the No Email delivery option do not receive special notices.

Only group owners or moderators can send special notices. Special notices typically are used for significant group announcements.


A group within another group. Members of a subgroup must also be members of the parent (primary) group. A subgroup typically contains a subset of the members of the parent group.

Restriction: Subgroups can be created only in Premium and Enterprise groups. Exception: Free groups that were created before January 15, 2020 can still create subgroups.

Subject tag

Text that is automatically added to the beginning of the subject line of group messages that are delivered by email. The tag is specified by the group’s owner and helps identify the group’s messages in members’ email applications.


See Member.


A collection of messages about a particular subject. It includes the initial message that was posted along with any replies to that message (and replies to those replies). In the archive on a group’s website, the topic is displayed with the initial message at the top of the page and replies expanded underneath it.

Note: In the past, the term thread was often used interchangeably with topic. However, topic is the preferred term.

Topic icons

See Member badges and topic icons.


See Topic.

Web/app notification

An automated alert message displayed by a website or mobile app outside of the web browser or app user interface (even when the website or app is not open). Sometimes referred to as push notifications, web/app notifications in provide users with timely information when certain activities occur in a group. The location and style of these notifications depend on the device’s operating system and the browser.


A repository of content on a group’s website, organized in pages. Wikis can be used to contain information that is revised frequently as well as to contain static information.

Revision history

Release date


06 December 2022

  • In the Subgroup entry, changed “Basic groups” to “Free groups” to reflect the current pricing and plan comparison pages.

11 November 2022

28 January 2022

  • Updated the copyright date to 2022 on the title page of the PDF version.

16 April 2021

19 March 2021

  • Updated the Bounce, bouncing definition to include the situation where messages containing new hashtags are bounced in groups that have the Hashtag Permissions setting, “Messages from members can only be tagged with existing hashtags, otherwise the message is bounced.”

08 January 2021

10 July 2020