A developer who handles the operations that occur at the back end of the program is called a back-end developer, Back end is the server side of the website or web application, Backend developer works on activities like creating Application Programming Interfaces, library creation and working with system components, The average salary of Backend developer in India is 5LPA, In this Article, we will deep dive into the Back End Developer Interview Question and Answers for Freshers.
What is Node Js?
Node Js is an open-source, cross-platform that works in a JavaScript runtime environment and library for web applications running outside the browser. Node Js utilizes Javascript as its scripting language and achieves high output via non-blocking Input Output and single-threaded event loop.
Libraries used in Node Js?
Express Js: Express Js is a node Js web application framework that provides a wide set of features to develop both mobile and web applications.
Mongoose: Mongoose is a node Js web application framework that makes the task easier of connecting an application to a database.
What Is NPM In Node.Js?
NPM stands for Node Package Manager. NPM provides some of the main functionalities. NPM works on an Online repository for node.js modules at <nodejs.org\>. It works as a command lineup to install packages, and do version management and dependency management of Node.js packages. Node Package Manager is bundled along with Node.js installable. For verifying the version we can use the following command-
$ npm --version
Node Package Manager (NPM) helps to install any Node.js module using:
$ npm install <Module Name>
Command to install Node.js web framework module called express-
$ npm install express
What are CSS Sprites?
Every image sends out an HTTP request separately. This means that a web page with a large number of photos takes to load. CSS sprites help to decrease the number of HTTP requests by minimizing the load time of a web page by combining more number of small pictures into one single image.
What is a Child_process module in Node.Js?
Node.js helps in the child processes in parallel processing with an event-driven model. It has three streams <child.stdin>, < child.stdout> , and <child.stderr>.
Node.js provides a <child_process> method that is used to create a child process.
exec – <child_process.exec> method is used to run a command in the console and buffers output.
spawn – <child_process.spawn> initialize a new process with a given command.
fork – <child_process.fork> is a special case of the spawn() method, It is used in creating a child process.
What Is Package.Json?
Package JSON (JavaScript Object Notation) is a plain text file that contains all metadata information about Node.js Project. It will be present in the root directory of every Node.js Package to describe its metadata in JSON format. The package treats every feature as a separate component.
What Is EventEmitter In Node.Js?
The Event module has an “EventEmitter” which is used to raise and handle over the custom events.
// Import events module
var events = require('events');
// Create an eventEmitter object
var eventEmitter = new events.EventEmitter();
When an EventEmitter has an error, it emits an “error” event. When a new listener is added, it fires a “newListener '' event and when a listener is removed, it fires a “removeListener '' event.
Conclusion :
The above-mentioned are the most important and Frequently asked Back End Developer Interview Questions and Answers for Freshers
Also, read our Article:
https://blog.skillsafari.in/back-end-developer-interview-questions-and-answers-for-freshers