Jquery

Question 1

What is jQuery?

Answer 1

A javascript library that adds functionality

Question 2

What is the jQuery selector function?

Answer 2

the $ sign

Question 3

What does the jQuery selector function return?

Answer 3

returns a jQuery object

Question 4

Why would someone use jQuery over vanilla Javascript?

Answer 4

cross-browser compatibility,

Question 5

What are some downsides from using jQuery over vanilla Javascript?

Answer 5

Need to load the massive jQuery library every time.

Question 6

Why do we use the < script > tag at the bottom of the body, instead of putting it inside the < head > tag?

Answer 6

HTML document loads from top to bottom

Question 7

How do you get the text out of an HTML element?

Answer 7

.html() or .text() method

Question 8

How do you get the value out of an HTML input field?

Answer 8

.val() method

Question 9

What’s the difference between .text() and .html()?

Answer 9

html() retrieves data from only the first element of that matched name
text() retrieves data from all elements of the given element name

Question 10

What does .on() do?

Answer 10

adds an event listener

Question 11

What is event bubbling?

Answer 11

The way in which nested events are handled. The order flow goes from most specific to least specific ->
child to parent

Question 12

What is the difference between event.target and event.currentTarget.

Answer 12

event.target is element that triggered the event.

currentTarget is the element the eventhandler is attached to

Question 13

What is the first argument the function setTimeout takes?

Answer 13

a function to be called after the timer

Question 14

If the second argument is not passed into the setTimeout function, what is the default value?

Answer 14

0

Question 15

What are some scenarios where setTimeout can be useful?

Answer 15

countdowns, game clocks, etc

Question 16

What does the setInterval function return?

Answer 16

an interval ID that identifies itself

Question 17

What argument does the clearInterval function take?

Answer 17

it takes the return value of setInterval

Question 18

What are some scenarios where setInterval can be useful?

Answer 18

countdowns, game clocks, etc

Question 19

What is the event loop?

Answer 19

A separate concurrent queue for code. when the call stack is empty, code in the event loop is pushed to the call stack.

Question 20

What does the term blocking mean?

Answer 20

something is preventing code in the call stack from running

Question 21

What is the call stack?

Answer 21

the data structure that arranges the order of actions to be taken by the code

Question 22

Which elements in a website are useful to create dynamically?

Answer 22

Things that rely on outside data, such as user input

Question 23

Why should you not create all elements dynamically?

Answer 23

can make your page open to attacks,

Question 24

What is a modal?

Answer 24

an overlay window with fixed position on the screen

Question 25

What are some use cases for modals?

Answer 25

something to grab the attention of the user,

Question 26

Why does a modal usually need to occupy the entire height and width of the viewport?

Answer 26

So that the user cannot click outside the modal area to avoid it

Question 27

Give two examples of media features that you can query in an @media rule.

Answer 27

width, height

Question 28

Which HTML meta tag is used in mobile-responsive web pages?

Answer 28

“viewport”