A shoutbox, saybox, tagboard, or chatterbox is a chat

Online chat

Online chat may refer to any kind of communication over the Internet, that offers an instantaneous transmission of text-based messages from sender to receiver, hence the delay for visual access to the sent message shall not hamper the flow of communications in any of the directions...

-like feature of some website

Website

A website, also written as Web site, web site, or simply site, is a collection of related web pages containing images, videos or other digital assets. A website is hosted on at least one web server, accessible via a network such as the Internet or a private local area network through an Internet...

s that allows people to quickly leave messages on the website, generally without any form of user registration.

In their simplest form, shoutboxes are simply lists of short messages, possibly with information about their authors. The page may be automatically refreshed after a certain interval, or polled dynamically in order to keep new messages visible. Older posts are often deleted after a certain number of messages have been written in order to preserve space on the server.