JavaScript P1

Question 1

JavaScript is related to Java T/F

Answer 1

False

Question 2

JavaScript is not______, it is ________.

Answer 2

compiled, interpreted

Question 3

Loosely-typed

Answer 3

variable types are assigned at runtime

Question 4

Undefined (keyword)

Answer 4

declared but not defined

Question 5

Not Defined (keyword)

Answer 5

not defined or declared

Question 6

Primitive Datatypes

Answer 6

undefined
boolean
number
string
bigint
symbol
null

Question 7

falsy types

Answer 7

-0
0
undefined
false
" "
NaN

Question 8

truthy types

Answer 8

true
1
object
everything else that isn’t falsy

Question 9

null

Answer 9

special primitive type having additional usage for its value: if object is not inherited, then null is shown

Question 10

typeof()

Answer 10

returns the type of the ‘thing’ in ()

Question 11

type coercion

Answer 11

changes the type of a variable when it is defined in another location

Question 12

Arrays

Answer 12

variable in length and type

Question 13

Functions: Three Invocations

Answer 13

Function form
Constructor form
Method form

Question 14

Function form

Answer 14

“this” refers to the global object

no overloading

Question 15

Constructor form

Answer 15

“this” refers to the object being made

Question 16

Method form

Answer 16

“this” refers to the object its based off

Question 17

Scopes: three types

Answer 17

Function Scope
Global Scope
Shadowing

Question 18

Function Scope

Answer 18

Things that are declared inside a function
use keyword var
if you don’t use ver, creates implicit global

Question 19

Global Scope

Answer 19

anything declared outside of a function

accessible anywhere

Question 20

Shadowing

Answer 20

if multiple variables have this same name, JS will use the one that was declared most recently

Question 21

____ does not escape blocks, ____ does

Answer 21

“let”, “var”

Question 22

Hoisting

Answer 22

moving declarations to top of scope

Question 23

var

Answer 23

a way to declare a variable
able to be reassigned
scope can be global or local

Question 24

let

Answer 24

preferred way to declare variables
able to be reassigned
scope is restricted to the block they were declared in

Question 25

const

Answer 25

variable can not be reassigned after declaration

scope is restricted to the block they were declared in

Question 26

prototype

Answer 26

mechanism by which JS objects inherit features from one another

Question 27

Arrow Notation

Answer 27

syntactically compact alternative to a regular function expression

Question 28

closure

Answer 28

an inner function that has access to the outer function variables