Node.js is a software platform for running server-side JavaScript. Node.js runs fast and scalable using Google's V8 JavaScript engine. Node.js is commonly used in areas such as web applications, APIs, microservices and data processing. Node.js is built on the JavaScript programming language and is specifically designed for the development of scalable and lightweight applications on a single processor core. Node.js uses an event-based model that provides concurrency and runs efficiently on processor cores. This allows Node.js to provide high performance and low memory consumption. Node.js can be used with several tools and modules. These include Express.js, Socket.io, Mongoose, Passport.js, Sequelize and many more. Express.js is a popular web framework for Node.js web applications. Socket.io is a module used for real-time web applications. Mongoose is an object data modeling tool for the MongoDB database. Passport.js is a tool for user authentication. Sequelize is an ORM (Object Relational Mapping) tool for SQL databases. Node.js is particularly favored in areas such as data processing, network operations and real-time operations. By using an event-based model, Node.js can perform network operations quickly and efficiently. Therefore, Node.js is particularly suitable for applications with heavy network traffic. For example, a chat application or a live streaming application. Node.js can also be used for data processing. Because Node.js provides high efficiency and low memory consumption, it is an ideal choice for performing operations on large datasets. For example, it can be used to analyze a log file or process data in a database. In conclusion, Node.js is a software platform built on the JavaScript programming language. It is used in combination with tools such as Express.js, Socket.io, Mongoose, Passport.js and Sequelize, making it the preferred choice for web applications, APIs, microservices and data processing.