Grochat is a simple Web chat system using PHP and Ajax. It offers a lightweight solution to webmasters who want to install a Web-based chat system without having to set up or customize a database for it. Instead, it uses text files to manage the content of the chat. It has multi-room support with a live count of the number of people in each room. A logout and "noop" system automatically keep the user's session up while the chat window is open, even if they are not typing anything into the chat. Public and private messaging. A private file send and receive system with file pooling server side. Works on IE and Firefox. An "on the fly" customisable layout. Multi-language and multi-skin support.