Node

Question 1

What is Node.js?

Answer 1

Node.js is a program that allows JavaScript to be run outside of a web browser.

Question 2

What can Node.js be used for?

Answer 2

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 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; a program written in a REPL environment is executed piecewise.

Question 4

When was Node.js created?

Answer 4

2009

Question 5

What back end languages have you heard of?

Answer 5

JavaScript, Java, PHP, Python, Ruby, C#, SQL, C++, C, Rust,

Question 6

What is a computer process?

Answer 6

The instance of a computer program that is being executed by one or many threads. It contains the program code and its activity. Depending on the operating system (OS), a process may be made up of multiple threads of execution that execute instructions concurrently.

Question 7

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

Answer 7

Full stack Web development is based on making multiple processes work together to form one application
To know what is involved for an application to run

Question 8

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

Answer 8

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 9

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

Answer 9

It’s global, it’s there and you can always access it?

Question 10

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

Answer 10

Array of strings

Question 11

What is a JavaScript module?

Answer 11

A single ‘.js’ file; The important part is file.

Question 12

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

Answer 12

exports, require, module, __filename, __dirname

Question 13

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

Answer 13

process and global

Question 14

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

Answer 14

Pick and choose what is available to other modules

To export functionality from one Node.js module to another Node.js module.

Question 15

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

Answer 15

require function

const add = require(‘./add’);

Question 16

What is the JavaScript Event Loop?

Answer 16

Look at call stack and task/callback queue, if stack empty, pushes first task/callback queue to call stack.

Question 17

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

Answer 17

blocking: code that is slow, on browser, prevents any other action while code is running.
non-blocking: asynchronous callbacks, it is run later?

Question 18

What is a directory?

Answer 18

A file system structure containing files and other directories; groups files together

Question 19

What is a relative file path?

Answer 19

location that is relative to current directory

path to file within same directory: file name

Question 20

What is an absolute file path?

Answer 20

contains the root element and the complete directory list to the file
path to file from the root directory to file name

Question 21

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

Answer 21

fs module

Question 22

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

Answer 22

fs.writeFile()

Question 23

Are file operations using the ‘fs’ module synchronous or asynchronous?

Answer 23

Both asynchronous and synchronous forms