Command Line

Question 1

What is a CLI?

Answer 1

Command line interface

Question 2

What is a GUI?

Answer 2

graphical user interface

Question 3

man

Answer 3

to get the manual on a command. Man cat for example.

Question 4

cat

Answer 4

print the contents of a file or concatenate multiple files.

Question 5

ls

Answer 5

display a list of contents of a directory.

Question 6

pwd

Answer 6

print working directory

Question 7

echo

Answer 7

can use echo to print messages and then create new txt files with that message

echo hello world > hello.txt

Question 8

touch

Answer 8

touch changes file timestamps. creates new files

Question 9

mkdir

Answer 9

make directory mkdir parent

mkdir -p parent/child/grandchild

Question 10

mv

Answer 10

move command, used to rename directorys or move.

mv pokiemans to pokemon

Question 11

rm

Answer 11

remove command

rm lol.txt

rm -r directoryname to delete all of its contents

Question 12

cp

Answer 12

copy

cp nameoffile newnameofcopy

Question 13

history

Answer 13

shows history of all recent command line commands to your terminal.

Question 14

what are 3 features of a great programmer.

Answer 14

laziness, hubris, impatience

Question 15

What is Node.js?

Answer 15

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 16

What can Node.js be used for?

Answer 16

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 17

What is a REPL?

Answer 17

A read–eval–print loop (REPL), also termed an interactive toplevel or language shell, is a simple interactive computer programming environment that takes single user inputs, executes them, and returns the result to the user;

console or gitbash

Question 18

When was Node.js created?

Answer 18

may 27 2009 by ryan dhal

Question 19

What back end languages have you heard of?

Answer 19

Java, ruby, python

Question 20

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

Answer 20

object that contains meta information, and control over the current node js process.

Question 21

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

Answer 21

just grab it, it always exists

Question 22

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

Answer 22

its an array of strings

Question 23

What is a JavaScript module?

Answer 23

in JavaScript, a “module” is a single .js file

Question 24

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

Answer 24

exports, __filname, __dirname, require, module

Question 25

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

Answer 25

process, console

Question 26

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

Answer 26

to export a desired item you attach to the exports property of the module.object

Question 27

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

Answer 27

``` module.exports = add const add = require('./add'); ```

Question 28

what is the javascript event loop?

Answer 28

function calls stack on top of the stack. Returns pop off stack. event loop has to wait for the stack to be clear to push the callback into the stack from the task queue.

Question 29

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

Question 30

What is a directory?

Question 31

What is a relative file path?

Answer 31

its a path to a file from where you are

Question 32

what is an absolute file path?

Answer 32

the root of the file system, just a slash.

Question 33

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

Answer 33

the fs module.

Question 34

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

Answer 34

fs.writeFile

Question 35

Are file operations using the fs module synchronous or asynchronous?

Answer 35

asynchronous and synchronous. fs.writeFileSync try catch if for synchronous code.

Question 36

What is NPM?

Answer 36

npm is a package manager for the JavaScript programming language maintained by npm. made up of 3 things: website, registry or the cli.

Question 37

What is a package?

Answer 37

a package is a directory with multiple files or modules and a package.json

Question 38

How can you create a package.json with npm?

Answer 38

npm init --yes

Question 39

What is a dependency and how to you add one to a package?

Answer 39

npm install jquery a dependency is third party code library that your application depends on to function.

Question 40

What happens when you add a dependency to a package with npm?

Answer 40

adds module to node_modules directory and the package.json is updated with the dependency

Question 41

how to vet a npm package.

Answer 41

visibility, documentation, userbase