Q1. What is Express.js?
Express.js is a fast, unopinionated, minimalist web framework for Node.js. It provides a robust set of features for building web and mobile applications, including HTTP utilities, middleware support, and routing. It simplifies the process of creating server-side applications by abstracting away complex Node.js code.
Q2. Why use Express.js with Node.js?
Express.js makes Node.js development faster and easier by providing a simple API for routing, middleware, and request/response handling. Without Express, you would need to write more low-level code using the native HTTP module. Express adds structure and helps in building scalable applications efficiently.
Q3. What are the key features of Express.js?
Key features include: robust routing, middleware support, template engine integration, static file serving, error handling, and easy database connectivity. It's also highly extensible through third-party middleware and supports various HTTP methods and URL patterns.
Q4. Is Express.js a framework or a library?
Express.js is a framework because it provides a structure and set of conventions for building applications. It controls the flow of the application and calls your code when needed (inversion of control). Libraries, on the other hand, are tools you call when you need them.
Q5. What type of applications can you build with Express.js?
You can build various applications including RESTful APIs, real-time applications (with Socket.io), single-page applications (as backend), microservices, and traditional web applications with server-side rendering using template engines like EJS or Pug.