How to make database in chat (socket.io)?

Question

JavaScript

Hello, I recently got a burning desire to write my own chat, it seems to work, but there is only one detail left - these are databases so that the history of correspondence is stored somewhere, googled, but found ready-made options and, in principle, understood little about them, tell me, more precisely specify what, how and where should be done to fasten this fucking database? :`(
PS The chat itself

Answer 1

Here in the screencast everything is explained in detail https://learn.javascript.ru/nodejs-screencast