Node.js

Question 1

What is Node.js?

Answer 1

Javascript not in a browser

Question 2

What can Node.js be used for?

Answer 2

To build backends

Question 3

What is a REPL?

Answer 3

A shortcut for read, eval, print, loop
Ie:
Google dev tools

Question 4

When was Node.js created?

Answer 4

In 2009 by Ryan Dahl

Question 5

What back end languages have you heard of?

Answer 5

Python, C++, Java, C, Ruby, Perl

Question 6

What is a computer process?

Answer 6

An instance of a program that is being executed

Question 7

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

Answer 7

100s or more

Question 8

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

Answer 8

So they know how much memory their app takes and the relationship between front end and backend

Question 9

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

Answer 9

A JavaScript object in Node that is a model of the computers Node.js that is currently running
(Similar to browser Window object)

Question 10

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

Answer 10

Just “process” because it’s global

Question 11

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

Answer 11

An array of strings

Question 12

What is a JavaScript module?

Answer 12

A way to separate applications into different files

Question 13

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

Answer 13

Dirname, filename, require, module, exports

Question 14

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

Answer 14

Process + URL

Question 15

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

Answer 15

It allows variables from other modules to be used

Question 16

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

Answer 16

Using the require function with a relative path as the argument

Question 17

What is the JavaScript Event Loop?

Answer 17

The system of managing the order of JavaScript processes (event queue, callback queue, call stack)

Question 18

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

Answer 18

Non-blocking = code can run synchronously

Blocking = whatever is currently running on the call stack

**use DMV analogy for A-synchronization

Question 19

What is a directory?

Answer 19

A place where paths for files are kept

Question 20

What is a relative file path?

Answer 20

A way to get from where you currently are, to another place

Question 21

What is an absolute file path?

Answer 21

Starting from anywhere, always starts with root

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

Both