Week 4 - Web

Question 1

What is an event handler?

Answer 1

something which can call code client side uploaded from the server

Question 2

What can we use to manipulate webpages?

Answer 2

DOM

Question 3

What does DOM stand for?

Answer 3

document object model

Question 4

Why can server side be any language possible?

Answer 4

only needs to recieve requests and send HTML pages

Question 5

Describe client-side web computation and processing?

Answer 5

• actions specific to a user
• local processing, fast response
• takes load off server
• reduces network load
• may incur local storage and processing overhead

Question 6

Describe server-side web computation and processing?

Answer 6

• common content generated on demand
• benefit for many users accessing same content
• higher overhead at server for each page/document to be dynamically generated

Question 7

What is dynamic typing?

Answer 7

when a type is assigned when a value is assigned

- but typing is strong

Question 8

What are javascript primitive types?

Answer 8

numbers
strings
booleans

Question 9

What are javascript trivial types?

Answer 9

null

undefined

Question 10

What are javascript composite types?

Answer 10

object

array

Question 11

Describe numbers in JS

Answer 11

8-byte floating point representation

Question 12

what does 3 === denote?

Answer 12

checks the type

strict equality

Question 13

what are the 3 variable keywords?

Answer 13

let
var
const

Question 14

what does == denote

Answer 14

converts type

Question 15

What is Node.js

Answer 15

it is an asynchronous event driven
JavaScript runtime
Node is designed to build scalable network
applications

Question 16

What happens on each connection in node?

Answer 16

Upon each connection the callback is fired,
but if there is no work to be done, Node will
sleep

Question 17

What does the DOM identify?

Answer 17

• the interfaces and objects used to represent and manipulate a document
• the semantics of these interfaces and objects
• the relationships among these interfaces and objects

Question 18

What is the JS document?

Answer 18

the html currently being displayed

Question 19

What is the JS window?

Answer 19

the OS window hosting the page

Question 20

What is the JS navigator?

Answer 20

the browser application in use

Question 21

What is the JS screen?

Answer 21

the physical monitor in use

Question 22

What JS do we use to find objects?

Answer 22

document.getElementById()

Question 23

What are some events that occur, that JS can be bound to?

Answer 23

• page starting loading
• use clicks a link
• user hovers their mouse over some content
• form submitted

Question 24

Where should javascript be included on a webpage?

Answer 24

just before

Question 25

Why should JS be at the bottom of the page?

Answer 25

allows page to load and as much of the DOM tree to be

created

Question 26

When are scripts executed?

Answer 26

executed in order of appearance during the

browsers HTML parsing process

Question 27

Where should you define all javascript elements? And why?

Answer 27

• in the HEAD section, since always processed before BODY
• so that the JavaScript objects that represent
  the body will have been created