75+ Node js interview questions and answers for experienced

Here are the basic and most common node js interview questions and answers for experienced professionals and freshers.

Node js basic interview questions

What is Node.js? Where can you use it?
Why use Node.js?
What are the features of Node.js?
Differentiate between JavaScript and Node.js
How node.js works?
What do you mean by the term I/O ?
What does event-driven programming mean?
Where can we use node.js?
What are the pros and cons of Node.js?
What is concept of Middle ware in Node.js?
How else can the JavaScript code below be written using Node.Js to produce the same output?
How do you update NPM to a new version in Node.js?

Advanced Node js technical interview questions

Why is Node.js Single-threaded?
Explain callback in Node.js.
What is callback hell in Node.js?
How do you prevent/fix callback hell?
Explain the role of REPL in Node.js.
What is the purpose of module.exports in Node.js?
Name the types of API functions in Node.js.
Which is the first argument typically passed to a Node.js callback handler?
What are the functionalities of NPM in Node.js?
What is the difference between Node.js and Ajax?
Explain chaining in Node.js.
What are “streams” in Node.js? Explain the different types of streams present in Node.js.
What are exit codes in Node.js? List some exit codes.
What are Globals in Node.js?
What is the difference between AngularJS and Node.js?
Why is consistent style important and what tools can be used to assure it?
What are the two types of API functions in Node.js ?
What is control flow function?
Why Node.js is single threaded?
Does nodejs run on windows?
Can you access DOM in node?
Using the event loop what are the tasks that should be done asynchronously?
Why node.js is quickly gaining attention from JAVA programmers?
What are the two arguments that async.queue takes?
What is an event loop in Node.js ?
Mention the steps by which you can async in Node.js?
How Node.js overcomes the problem of blocking of I/O operations?
What is the difference between Node.js vs Ajax?
What are the Challenges with Node.js ?
What does it mean “non-blocking” in node.js?
What is the command that is used in node.js to import external libraries?
Mention the framework most commonly used in node.js?
What is ‘Callback’ in node.js?
What is an error-first callback?
How can you avoid callback hells?
What are Promises?
What tools can be used to assure consistent style? Why is it important?
When should you npm and when yarn?
What’s a stub? Name a use case!
What’s a test pyramid? Give an example!
What’s your favorite HTTP framework and why?
How can you secure your HTTP cookies against XSS attacks?
How can you make sure your dependencies are safe?
How secure node.js applications ? Can we add more security ?
What are best node js frameworks
Express.js
Sails.js
How to connect database in node js ?
What are different databases supported by Nodejs ?
What is purpose of Buffer class in Node?
What is Piping in Node?
Which module is used for file based operations?
Which module is used for buffer based operations?
Which module is used for web based operations?
What is Chaining in Node?
How can you Tracing in Node js ?
How will you debug an application in Node.js?
What is package.json?
Explain libuv ?
Differentiate between spawn() and fork() methods in Node.js?
Decribe the exit codes of Node.js.
Is cryptography supported in Node.js?
Explain the concept of Punycode in Node.js?? Where can you use it?
Why use Node.js?
What are the features of Node.js?
Differentiate between JavaScript and Node.js
How node.js works?
What do you mean by the term I/O ?
What does event-driven programming mean?
Where can we use node.js?
What are the pros and cons of Node.js?
What is concept of Middle ware in Node.js?
How else can the JavaScript code below be written using Node.Js to produce the same output?
How do you update NPM to a new version in Node.js?
Why is Node.js Single-threaded?
Explain callback in Node.js.
What is callback hell in Node.js?
How do you prevent/fix callback hell?
Explain the role of REPL in Node.js.
What is the purpose of module.exports in Node.js?
Name the types of API functions in Node.js.
Which is the first argument typically passed to a Node.js callback handler?
What are the functionalities of NPM in Node.js?
What is the difference between Node.js and Ajax?
Explain chaining in Node.js.
What are “streams” in Node.js? Explain the different types of streams present in Node.js.
What are exit codes in Node.js? List some exit codes.
What are Globals in Node.js?
What is the difference between AngularJS and Node.js?
Why is consistent style important and what tools can be used to assure it?
What are the two types of API functions in Node.js ?
What is control flow function?
Why Node.js is single threaded?
Does nodejs run on windows?
Can you access DOM in node?
Using the event loop what are the tasks that should be done asynchronously?
Why node.js is quickly gaining attention from JAVA programmers?
What are the two arguments that async.queue takes?
What is an event loop in Node.js ?
Mention the steps by which you can async in Node.js?
How Node.js overcomes the problem of blocking of I/O operations?
What is the difference between Node.js vs Ajax?
What are the Challenges with Node.js ?
What does it mean “non-blocking” in node.js?
What is the command that is used in node.js to import external libraries?
Mention the framework most commonly used in node.js?
What is ‘Callback’ in node.js?
What is an error-first callback?
How can you avoid callback hells?
What are Promises?
What tools can be used to assure consistent style? Why is it important?
When should you npm and when yarn?
What’s a stub? Name a use case!
What’s a test pyramid? Give an example!
What’s your favorite HTTP framework and why?
How can you secure your HTTP cookies against XSS attacks?
How can you make sure your dependencies are safe?
How secure node.js applications ? Can we add more security ?
How to connect database in node js ?
What are different databases supported by Nodejs ?
What is purpose of Buffer class in Node?
What is Piping in Node?
Which module is used for file based operations?
Which module is used for buffer based operations?
Which module is used for web based operations?
What is Chaining in Node?
How can you Tracing in Node js ?
How will you debug an application in Node.js?
What is package.json?
Explain libuv ?
Differentiate between spawn() and fork() methods in Node.js?
Decribe the exit codes of Node.js.
Is cryptography supported in Node.js?
Explain the concept of Punycode in Node.js?