Node.js fundamentals: Build scalable applications

Node.js is an event-driven and asynchronous JavaScript runtime environment built for scalable network applications. It utilizes non-blocking I/O, allowing for efficient operations and more affordable development of scalable systems. Core concepts include modules, Event Emitters, Buffer, and REPL. Modules are blocks of code that provide functionality, while Event Emitters handle input interactions on an application from end users. Buffer manages TCP streams and read-write operations on file systems requiring binary code, and REPL is a programming environment for testing simple TypeScript code. Node.js offers benefits such as high performance and scalability, a large and active community, full-stack JavaScript development, and cross-platform compatibility. It can be used for web development with frameworks like Express.js or Nest.js, command-line tools, data access, and serverless functions. Deploying Node.js applications can be challenging, but platforms like Netlify offer solutions to overcome these issues.