Interview Questions
The MEAN stack is a set of JavaScript technologies for building web applications: MongoDB
(database), Express.js (server framework), Angular (front-end framework), and Node.js
(server runtime).
MongoDB is a NoSQL database that uses flexible, JSON-like documents, whereas relational
databases use fixed schemas and tables.
Express.js handles server-side logic, routing, and middleware in Node.js applications.
Node.js uses non-blocking I/O with callbacks, promises, and async/await to handle
asynchronous tasks.
ngRoute is used in AngularJS (1.x) for routing, while @angular/router is the official
routing module for Angular (2+), offering more features and better support.
A RESTful API uses HTTP methods and status codes to perform CRUD operations. Express.js
creates RESTful APIs by defining routes and handling requests to interact with data.
Angular handles form validation using built-in directives like ngModel and formControl, and
custom validators to ensure input meets specified criteria.
Environment variables store configuration values like database URLs and API keys. In a MEAN
stack app, they are accessed using process.env in Node.js and can be managed with libraries
like dotenv.
app.use() is used to mount middleware functions that process requests and responses, or to
handle specific routes.
Angular modules group related components, directives, pipes, and services into cohesive
blocks, facilitating better organization and dependency management.
