node.js

Question 1

What is Node.js?

Answer 1

Node.js is a program that allows JavaScript to be run outside of a web browser. It is commonly used to build back ends for Web applications, command-line programs, or any kind of automation that developers wish to perform.

Question 2

What can Node.js be used for?

Answer 2

Node.js is a platform built on Chrome’s JavaScript runtime for easily building fast, scalable network applications. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.

Event-driven means that the server only reacts when an event occurs. This allow us to create high performance, highly scalable, “real-time” applications.

Question 3

What is a REPL?

Answer 3

read-eval-print-loop. A simple interactive computer programming environment that takes single user inputs, executes them, and returns the result to the user

Question 4

When was Node.js created?

Answer 4

2009

Question 5

What back end languages have you heard of?

Answer 5

Python, Ruby, Java

Question 6

What is a computer process?

Answer 6

the instance of a computer program that is being executed by one or many threads. While a computer program is a passive collection of instructions, a process is the actual execution of those instructions.

Question 7

Roughly how many computer processes are running on your host operating system (Task Manager or Activity Monitor)?

Answer 7

150

Question 8

Why should a full stack Web developer know that computer processes exist?

Answer 8

full-stack development is based on making multiple processes work together

Question 9

What is the process object in a Node.js program?

Answer 9

The process object is a global that provides information about, and control over, the current Node.js process.

Question 10

How do you access the process object in a Node.js program?

Answer 10

process

Question 11

What is the data type of process.argv in Node.js?

Answer 11

array

Question 12

What is a JavaScript module?

Answer 12

an individuall js file

Question 13

What values are passed into a Node.js module’s local scope?

Answer 13

The values passed in the module wrapper: exports, require, module, __filename, __dirname

Question 14

Give two examples of truly global variables in a Node.js program.

Answer 14

global and process

Question 15

What is the purpose of module.exports in a Node.js module?

Answer 15

export code from a file to allow use in a different file

Question 16

How do you import functionality into a Node.js module from another Node.js module?

Answer 16

module.exports & require

Question 17

What is the JavaScript Event Loop?

Answer 17

a que for the call back functions run by the web API. Once the call stack is empty it will process the items.

Question 18

What is different between “blocking” and “non-blocking” with respect to how code is executed?

Answer 18

blocking refers code that blocks other code from running

Question 19

What is a directory?

Answer 19

a file system cataloging structure which contains references to other computer files, and possibly other directories.

Question 20

What is a relative file path?

Answer 20

A relative path is a way to specify the location of a directory relative to another directory.

Question 21

What is an absolute file path?

Answer 21

An absolute path refers to the complete details needed to locate a file or folder, starting from the root element

Question 22

What module does Node.js include for manipulating the file system?

Answer 22

fs

Question 23

What method is available in the Node.js fs module for writing data to a file?

Answer 23

writeFile

Question 24

Are file operations using the fs module synchronous or asynchronous?

Answer 24

asynchronous