Node

Question 1

What is Node.js?

Answer 1

program that lets JavaScript to be run outside of a web browser

Question 2

What can Node.js be used for?

Answer 2

build back end for Web applications, command-line programs, or any kind of automation that developers wish to perform

Question 3

What is a REPL?

Answer 3

read-eval-print loop

takes input, reads and executes it, then 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, C, C++, java, C#, PHP, JavaScript, Go, Rust, Assembly

Question 6

What is a computer process?

Answer 6

a computer program being executed

Question 7

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

Answer 7

~300

Question 8

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

Answer 8

Full stack Web development is based on making multiple processes work together to form one application, so having at least a cursory awareness of computer processes is necessary

Question 9

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

Answer 9

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

console.log(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

a single JavaScript file

Question 13

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

Answer 13

exports, require, module, __filename, __dirname

Question 14

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

Answer 14

process and console

Question 15

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

Answer 15

instructions/command that tells node.js which bits of code can be exported so that other files may access them

Question 16

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

Answer 16

require(./filename)

./ looks in current directory

Question 17

What is the JavaScript Event Loop?

Answer 17

thing that looks at the stack and pushes first item in the queue to the stack IF the stack is empty

Question 18

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

Answer 18

blocking occurs when an item in the stack takes a while and stalls the program - this can happen in synchronous codes
non-blocking executes “multiple threads” at a time by utilizing browsers to manage asynchronous codes (callbacks)

Question 19

What is a directory?

Answer 19

a collection of files

Question 20

What is a relative file path?

Answer 20

path to the file from the current directory

Question 21

What is an absolute file path?

Answer 21

path to the file from the root

filepath starts with ‘/’ and only that

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

fs.writeFile

Question 24

Are file operations using the fs module synchronous or asynchronous?

Answer 24

both, they have synchronous and asynchronous methods