What does the chat room mean?
A chat room is a designated virtual channel where users communicate with each other over the Internet, traditionally in plain text only. More recent developments in web technology now allow the transmission of images and emoticons also in a chat room. The term can refer to online chat, instant messaging, and online forums using synchronous or asynchronous conferencing. Some chat rooms require a username and password combination to connect or join a conversation, which helps maintain user privacy.
Techopedia explains the chat room
In 1974, the first online conferencing system was developed by David Wooley and Doug Brown. It allowed five people per channel to communicate with each other and it offered multiple channels. When a user typed a message, each character was displayed on other users’ screens as they were typed in real time. In 1980, CompuServe made the CompuServe CB Simulator, the first online chat system made available to the public. From mIRC, one of the first popular chat clients, to Yahoo! Messenger, Skype and a host of messaging apps available on major mobile platforms, the chat room has evolved into an indispensable tool for modern communication.