Node intro, process, process.argv, modules, fs-read/writefile

Question 1

What is Node.js?

Answer 1

JavaScript runtime built on Chrome’s V8 JavaScript engine

Question 2

What can Node.js be used for?

Answer 2

To build scalable network applications

Write your code in JavaScript and execute it with node

Question 3

What is REPL?

Answer 3

Read-eval-print loop

Simple interactive computer programming environment that takes single user inputs, executes them, and returns the result to the user

A program written in a REPL environment is executed piecewise

Question 4

What is a computer process?

Answer 4

A process is the instance of a computer program that is being executed by one or many threads. It contains the program code and its activity.

Question 5

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

Answer 5

Full stack web development is based on making multiple processes work together to form one application

Question 6

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

Answer 6

The process object is a global that provides information about, and control over, the current Node.js process. As a global, it is always available to Node.js applications without using require()

Question 7

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

Answer 7

It’s included in the global. You can use it any time by name.

Question 8

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

Answer 8

An array of strings

Question 9

What is a JavaScript Module?

Answer 9

A JavaScript module is a example.js file

Question 10

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

Answer 10

__dirname
The directory of the current model

__filename
The file name of the current module

exports
A reference to the module.exports (exports a file)

module
A reference to the current module

require()
Used to import modules, JSON, and local files

Question 11

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

Answer 11

global.process

Global.global

Question 12

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

Answer 12

It allows other files/nodes to access the the exported function, string, variable etc

Question 13

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

Answer 13

Const name = require(‘.module’)

Use the require function

Question 14

What is a directory?

Answer 14

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

A file to point to other files, a place in a file system that stores other files

Question 15

What is a relative file path?

Answer 15

A relative file path is a folder within the current directory

Question 16

What is an absolute file path?

Answer 16

An absolute file path is a folder or file outside the current directory

Anything that starts with a forward slash /

Question 17

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

Answer 17

The fs module

Question 18

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

Answer 18

the writeFile method

Question 19

Are file operations using the fs module synchronous or asynchronous?

Answer 19

writeFile is Asynchronous

writeFileSync is Synchronous