Top 20 Node.js Interview Questions for Freshers
1) What is NodeJS?
Node.js can be simply explained as it is a concept of two outcomes: runtime environment and JavaScript library. So basically, node.js will enable you to use javascript beyond the browser. It can make Javascript like 'go anywhere Javascript'.
2) What is NPM?
Javascript operates in a runtime environment with the help of node js having its own package manager, this package manager is called NPM.
3) What is CLI in Node.js?
One of the vital reasons for Node.js getting popular is its 900000 packages connected to a large ecosystem. CLI is a command-line interface that will allow you to automate your tasks by taking advantage of this vast ecosystem. Not only that, by writing CLI you can differentiate your proposed packages among the ecosystem.
4) In which Language Node Js is written?
Node.js shows compatibility with three types of language
- C
- C++
- Javascript
5) Who is the author of Node Js?
Ryan Dahl is the author of Node.js it was almost 13 years back when the javascript environment was introduced to the world. Initially, Node is was supported by Linux and Mac OS X but later it was sponsored by Joyent.
6) What is a Javascript Engine?
Javascript engine is used to run the java code in the browser so you can define a javascript engine as a computer program that is used to perform the java code. Initially, it was just used for interpretation and progressively it improved and got evolved. Generally, all browsers have one dealer and he is the one who develops the javascript engine.
7) What is a V8 Engine?
In 2008 when google chrome was launched time chrome also introduced its project of the V8 engine. It is an open-source network that can be written in the c++ language.
8) What is ECMAScript?
Ecmascript first appeared in 1997, which was specified and developed by Esma internationals. Evmascriot is also a programming language, which developed various other scripts like Jscript, ActionScript, and the most popularly used javascript.
9) How can you check the installed version of Node Js?
For that, you need to install NPM which is a package manager. The second thing you will need is to have a node in your computer, you can check installed NPM and node by just typing simple commands. Now carry the following steps
Open the windows command prompt
Open command-line tool line Babun, Powershell, ConEmu, etc.
Type node-v which will display your current version of Node Js.
10) What are Modules in Node Js?
Modulus is various commands used in node js to perform tasks like addition, subtraction, division, multiplication, etc. Ins short you can do maths in js using modulus.
11) What are the common Modules?
Arithmetic operations ( addition, subtraction, multiplication, division), exponentials, increment, and decrement are various common modulus in js.
12) What require() is used in Node Js?
Modulus is operated by two main managing modules
The Require module
The module module
Both of them are available on a global scope.
13) What the module. exports in Node Js?
The module. exports is a default application that can be found in every js file of Node js.
14) Is Node Js Single-threaded?
Node Js is single-threaded but it is non-blocking as well, it means that while operating node js various functions like callbacks is carried out in the background which is carried out using different threads or multiple threads.
15) Node JS Vs Ruby
| Feature | Node JS | Ruby On Rails |
| Written In | C, C++, JavaScript | Ruby |
| Operating System | Solaris, OpenBSD, FreeBSD, Linux, Mac, MS, webOS and nonstops | Cross-Platform |
| Type | Event-driven networking | Web application framework |
| License | MIT | MIT |
| Performance | High | Low |
| Popularity | Popular for its features | Yet to be popular |
| Documentation | Available | Lack of documentation |
| Consistency | Inconsistent | Consistent structure |
| Complexity | Easy to implement | Complex implementation |
16) What are the events?
The event can be explained as activities carried out. For example, when you open a file it is an event when you close a file it is an event.
In Node js, there is a defaulted module named "Events" with which you can carry various activities like create, fire, listen, etc.
17) What the event loop in Node Js?
Non-blocking operations in Node Js are carried out with the help of the event loop.
18) How to create a simple server in Node js that returns Hello World?
Certain steps are needed to be carried out for this operation:
Import the module which is required.
Create the server using HTTP.createServer().
Test the request and wait for a response
19) Difference between the cluster and child_process modules?
- A cluster is when one master program is running two or more nodes at a single running time.
- A child process simply starts a new script on the system, it is quite similar to the cluster but in a different language.
20) How to stop the master process without suspending all of its child processes?
Upstart is a process management system with which you can stop the master process. Generally when the master process is stopped or killed the child process still continues to work.
Thankyou For Reading
No comments:
Post a Comment