Node.js Online Quiz

Following quiz provides Multiple Choice Questions (MCQs) related to Node.js Framework. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.

Q 1 - Why code written in Node.JS is pretty fast although being written in JavaScript?

A - Node.JS internally converts JavaScript code to Java based code and then execute the same.

B - Node.JS internally converts JavaScript code to C based code and then execute the same.

C - Being built on Google Chrome's V8 JavaScript Engine.

D - None of the above.

Answer : C

Explanation

Being built on Google Chrome's V8 JavaScript Engine, Node.js library is very fast in code execution.

Q 2 - Which of the following is true about package.json?

A - package.json is present in the root directory of any Node application/module.

B - package.json is used to define the properties of a package.

C - package.json can be used to update dependencies of a Node application.

D - All of the above.

Answer : D

Explanation

package.json is present in the root directory of any Node application/module and is used to define the properties of a package. It can also be used to update dependencies of a Node application.

Q 3 - Which of the following is true with respect to Node.

A - Every API of Node js are asynchronous.

B - Node being a single thread, and uses async function calls to maintain the concurrency.

C - Node thread keeps an event loop and whenever any task get completed, it fires the corresponding event which signals the event listener function to get executed.

D - All of the above.

Answer : D

Explanation

Node js is a single threaded application but it support concurrency via concept of event and callbacks. As every API of Node js are asynchronous and being a single thread, it uses async function calls to maintain the concurrency. Node uses observer pattern. Node thread keeps an event loop and whenever any task get completed, it fires the corresponding event which signals the event listener function to get executed.

Q 4 - Which of the following is true about Chaining streams?

A - Chanining is a mechanism to connect output of one stream to another stream and create a chain of multiple stream operations.

B - Chanining is normally used with piping operations.

C - Both of the above.

D - None of the above.

Answer : C

Explanation

Chanining is a mechanism to connect output of one stream to another stream and create a chain of multiple stream operations. It is normally used with piping operations.

Q 5 - Which of the following is true about clearTimeout(t) global function?

A - The clearTimeout( t ) global function is used to stop a timer that was previously created with setTimeout().

B - The clearTimeout( t ) function returns an opaque value that represents the timer which can be used to clear the timer.

C - Both of the above.

D - None of the above.

Answer : A

Explanation

The clearTimeout( t ) global function is used to stop a timer that was previously created with setTimeout(). Here t is the timer returned by setTimeout() function.

Q 6 - Which of the following code prints memory usage?

A - console.log(process.memoryUsage());

B - console.log('Current version: ' + process.memory());

C - console.log('Current version: ' + process.getMemory());

D - None of the above.