User:FeRDNYC/Conversation threading

Conversation threading refers to a method of facilitating online communication among multiple participants, in which responses to an initial message or topic are grouped or arranged together visually. It is a feature offered by many email clients to keep conversations together rather than separating sent and received messages, popularized especially by Google's web-based email service Gmail. It is also a feature of many bulletin board, newsgroup, or Internet forum systems, or of the client software used to access their messages.

Messages are usually grouped visually by topic and arranged chronologically, with newer responses displayed beneath previous messages. A set of messages grouped in this way is called a topic thread, comment thread, or simply "thread". A discussion forum, e-mail client, social networking site such as Facebook, or news client that groups related messages together in this manner is said to have "threaded topics". The thread index is typically arranged reverse-chronologically by date of last reply, so that the most recently active threads appear first.

In some systems, the user may reply to any specific previous message. (In others, all responses are followups to the initial topic/message.) As a result, there can be a hierarchy of discussions within the thread topic. Various types of software may allow this hierarchy to be displayed in what's called Threaded Mode. (The alternative being Linear Mode, which typically shows all of the posts in date order, regardless of who may have specifically replied to whom.)