1 $Which JavaScript engine is Node.js built upon?$

A.

JavaScriptCore

B.

SpiderMonkey

C.

Chakra

D.

V8

2 $Which of the following best describes the nature of Node.js?$

A.

Single-threaded and blocking

B.

Multi-threaded and non-blocking

C.

Single-threaded and non-blocking

D.

Multi-threaded and blocking

3 $Who created Node.js?$

A.

Tim Berners-Lee

B.

Brendan Eich

C.

Jordan Walke

D.

Ryan Dahl

4 $What does REPL stand for in the context of Node.js?$

A.

Read Evaluate Process Loop

B.

Run Execute Print Loop

C.

Read Execute Process List

D.

Read Eval Print Loop

5 $Which command allows you to enter the Node.js REPL environment in a terminal?$

A.

node

B.

npm start

C.

repl

D.

js

6 $In the Node.js REPL, what does the underscore variable (_) represent?$

A.

The last evaluated result

B.

An undefined variable

C.

The current directory

D.

The global scope

7 $Which command is used to initialize a new Node.js project and create a package.json file?$

A.

npm install

B.

npm init

C.

npm start

D.

npm new

8 $Which flag can be used with 'npm init' to skip the questionnaire and use default values?$

A.

--default

B.

-y

C.

-f

D.

--skip

9 $Where does npm install the dependencies for a local project by default?$

A.

/usr/local/lib

B.

node_modules

C.

global_modules

D.

npm_packages

10 $Which file stores the metadata and dependency list for a Node.js project?$

A.

node_modules

B.

config.xml

C.

index.js

D.

package.json

11 $Which function is used to include modules in Node.js?$

A.

require()

B.

fetch()

C.

include()

D.

import()

12 $Which of the following is a Core Module in Node.js?$

A.

express

B.

lodash

C.

fs

D.

mongoose

13 $How do you export a function or object from a module in Node.js using CommonJS?$

A.

return module

B.

module.exports

C.

export default

D.

exports.module

14 $Which syntax is correct to import a local module located in the same directory?$

A.

import moduleName

B.

require('/moduleName')

C.

require('moduleName')

D.

require('./moduleName')

15 $What is the purpose of the 'events' module in Node.js?$

A.

To handle and trigger events

B.

To handle HTTP requests

C.

To handle file operations

D.

To stream data

16 $Which class is the primary component of the 'events' module?$

A.

EventListener

B.

EventHandler

C.

EventDispatcher

D.

EventEmitter

17 $Which method of EventEmitter is used to register a listener for an event?$

A.

listen()

B.

emit()

C.

trigger()

D.

on()

18 $Which method of EventEmitter causes an event to occur?$

A.

dispatch()

B.

fire()

C.

call()

D.

emit()

19 $What is a 'callback' in Node.js?$

A.

A blocking function

B.

A function passed as an argument to be executed later

C.

A global variable

D.

A recursive loop

20 $What is the convention for the first argument of a Node.js callback function?$

A.

The result data

B.

The configuration object

C.

The error object (or null)

D.

The callback function itself

21 $What is 'Callback Hell'?$

A.

Deeply nested callbacks making code hard to read

B.

When a callback never executes

C.

A security vulnerability

D.

A syntax error in callbacks

22 $Which method is used to read a file asynchronously in Node.js?$

A.

fs.open()

B.

fs.read()

C.

fs.readFile()

D.

fs.readFileSync()

23 $What happens if you use 'fs.writeFile()' on an existing file?$

A.

It creates a backup copy

B.

It replaces the file content

C.

It appends data to the end

D.

It throws an error

24 $Which 'fs' method is used to add data to a file without overwriting it?$

A.

fs.insert()

B.

fs.addFile()

C.

fs.writeAfter()

D.

fs.appendFile()

25 $How do you delete a file using the 'fs' module?$

A.

fs.unlink()

B.

fs.erase()

C.

fs.remove()

D.

fs.delete()

26 $Which method converts a JavaScript object into a JSON string?$

A.

JSON.stringify()

B.

JSON.convert()

C.

JSON.toString()

D.

JSON.parse()

27 $Which method parses a JSON string into a JavaScript object?$

A.

JSON.stringify()

B.

JSON.parse()

C.

JSON.decode()

D.

JSON.objectify()

28 $What is a Stream in Node.js?$

A.

A database connection

B.

A continuous flow of data handled piece by piece

C.

A large file stored in memory

D.

A static HTML page

29 $Which type of stream can generally be used to read data from a source?$

A.

Duplex

B.

Readable

C.

Transform

D.

Writable

30 $What is the purpose of the 'pipe()' method in streams?$

A.

To connect a readable stream to a writable stream

B.

To pause the stream

C.

To convert stream to buffer

D.

To delete the stream

31 $Which module allows you to work with file paths specifically?$

A.

fs

B.

http

C.

url

D.

path

32 $Which Node.js module provides compression and decompression functionality?$

A.

zlib

B.

crypto

C.

compress

D.

zip

33 $Which function creates a stream that compresses data using Gzip?$

A.

zlib.compress()

B.

zlib.createGzip()

C.

zlib.zip()

D.

zlib.gzip()

34 $What are the three states of a Promise?$

A.

Pending, Fulfilled, Rejected

B.

True, False, Null

C.

Start, Stop, Pause

D.

Running, Waiting, Dead

35 $Which method is used to handle the successful resolution of a Promise?$

A.

.done()

B.

.catch()

C.

.then()

D.

.finally()

36 $Which method is used to catch errors in a Promise chain?$

A.

.catch()

B.

.error()

C.

.then()

D.

.fail()

37 $What does the 'async' keyword do when placed before a function?$

A.

It makes the function run in a separate thread

B.

It makes the function synchronous

C.

It pauses the event loop

D.

It ensures the function returns a Promise

38 $The 'await' keyword can only be used inside which type of function?$

A.

async functions

B.

Synchronous functions

C.

Callback functions

D.

Any function

39 $What is the benefit of using async/await over callbacks?$

A.

It writes asynchronous code that looks synchronous and is easier to read

B.

It runs faster

C.

It bypasses the V8 engine

D.

It creates multi-threading

40 $What is the global object in Node.js equivalent to 'window' in browsers?$

A.

document

B.

global

C.

process

D.

root

41 $Which global variable holds the directory name of the current module?$

A.

__filename

B.

module.path

C.

__dirname

D.

process.cwd()

42 $Which method checks if a file exists in Node.js (Modern approach)?$

A.

fs.check()

B.

fs.validate()

C.

fs.exists()

D.

fs.access()

43 $What is a 'Duplex' stream?$

A.

A stream that can only read

B.

A stream that can only write

C.

A stream that can both read and write

D.

A stream that compresses data

44 $What is the file extension typically used for a file containing CommonJS module code?$

A.

.mjs

B.

.js

C.

.ts

D.

.json

45 $How can you install a package globally using npm?$

A.

npm install package --all

B.

npm global install package

C.

npm install package -g

D.

npm add package global

46 $What does 'npm' stand for?$

A.

Node Process Manager

B.

Node Package Manager

C.

Node Project Manager

D.

New Package Module

47 $When using 'fs.createReadStream', which event is fired when the file is completely read?$

A.

close

B.

finish

C.

end

D.

done

48 $In a Promise, what happens if you return a value in a .then() block?$

A.

The value is ignored

B.

It throws an error

C.

The promise chain stops

D.

The next .then() receives it as a resolved value

49 $What is the main advantage of Streams over reading files into memory?$

A.

Streams are synchronous

B.

Streams sort data automatically

C.

Streams encrypt data automatically

D.

Streams use less memory (memory efficiency)

50 $Which core module allows you to create a web server?$

A.

http

B.

url

C.

fs

D.

net

Unit 1 - Practice Quiz