.env is a zero-dependency module that loads environment variables from a .env file into process.env.
Bcrypt is a library that help you easily hash passwords and compare them in Node.js .
UUID is a unique random ids values generator. It generates strong random values.
Axios is a popular promise based HTTP client for the browser and node.js
Socket.io enables realtime, bi-directional communication between web clients ans servers.
Moment.js is a date library for parsing, validating, manipulating and formatting dates.
Lodash is very useful, when working with numbers, arrays, objects, string,etc.