Module 3

Question 1

What cache means in English?

Answer 1

A collection of items stored somewhere for later use.

Ex: A weapon cache.

Question 2

What is cache in a computer?

Answer 2

A place where data is stored for later fast reading.

Question 3

Which one of the following is not a recommended method of debugging code?

1. Review your code for errors
2. Google for possible solutions
3. Clear your cache
4. Utilize the nav element

Answer 3

4. Utilize the nav element

Question 4

What AJAX stands for?

Answer 4

Asynchronous JavaScript and XML

Question 5

Why AJAX is asynchronous?

Answer 5

Because a request can be done indepent of the request of a full webpage.

Ex: a request can be done to change the video shown of a webpage without requesting a full new webpage.

Question 6

How AJAX acomplish its task?

Answer 6

By combining JavaScript and XML.

Question 7

What API stands for?

Answer 7

Application Programming Interface.

Question 8

What JSON stands for?

Answer 8

JavaScript Object Notation

Question 9

What are the two elements in JSON used to describe the format of data?

Answer 9

Key/Value Pairs and Ordered List of Values.

Question 10

Give an example of Key/Value Pair in JSON.

Answer 10

Key: value

“Age:”: 15
“Name”: “Angela Smith”

Question 11

Give an example of Ordered List of Values.

Answer 11

name of ordered list: [value1, value2, value3]

“MajoAreasOfStudy”: [“Physics”, “Computer Science”]

Or

{
“student”:
{
“Name”: “Angela Smith”,
“Age”: 15,
“GradePointAverage”: 3.25,
“MajorAreasOfStudy”: [“Physics”, “Computer Science”]
}
}

Question 12

What XHR stands for?

Answer 12

XML HTTP Request.

Question 13

What is XHR?

Answer 13

XHR is a set of APIs used by script languages to transfer XML to and from a web server using HTTP.

Question 14

What kind of data XHR can be used to transfer?

Answer 14

HTML, XML, JSON, and more.

Question 15

What are the main features of the Ruby programming language?

Answer 15

Suitable for writing scripts as well as robust object-oriented programs.

Question 16

What is Ruby on Rails?

Answer 16

A webaplication framework that is written in Ruby.

Question 17

What State means in English?

Answer 17

The condition or status of a thing at a specific point in time.

Question 18

What is a Distributed System?

Answer 18

A computing system in which the various elements of the system are located on different computers on a network.

Question 19

What is a Distributed Program?

Answer 19

Programs designed to work together in a Distributed System.

Ex: “client/server”

Question 20

What Distributed Programs need to coordinate their actions?

Answer 20

A protocol.

Question 21

What means to say that HTTP is a stateless protocol?

Answer 21

It means that HTTP doens’t account for the fact that the state of some information on the server and the client can change states and become unsynchronized.

Question 22

Give an example of how HTTP can be stateless.

Answer 22

A client request a list of costumers of a server. The server respond with the list of costumers. Later the list of costumers is updated in the server and the client change it own version of the list on the client side. Now the two lists are unsynchronized.

Question 23

What is the difference between “stateful” and “stateless”?

Answer 23

Stateless means “neither the client nor the server are aware of the state of the other at any particular point in time” and stateful means “the various actions that take place on the server and the client are remembered and accounted for”.

Question 24

Give an example of a definition of a function in JavaScript.

Answer 24

function add(num1, num2)
{
return num1 + num2
}

Question 25

What is a method in JavaScript?

Answer 25

A set of code, associated with an object, that is performed on the object itself.

Question 26

Give an example of a method in JavaScript.

Answer 26

const person = {
firstName: “John”,
lastName: “Doe”,
id: 5566,
fullName: function() {
return this.firstName + “ “ + this.lastName;
}
};

Question 27

What the Document.getElementById method does?

Answer 27

Returns an html element by using its id attribute.

Question 28

What REPL stands for?

Answer 28

read-eval-print-loop.

Question 29

What is REPL?

Answer 29

Interactive computer programming enviroment that allows developers to write code and see a near-immediate result.

Question 30

What DOM stands for?

Answer 30

Document Object Model.

Question 31

What is DOM?

Answer 31

Is the interface for HTML.

Question 32

HTTP is a _____ protocol.

1. stateless
2. stateful

Answer 32

1. stateless

Question 33

Which one of the following terms is best defined as “a collection of methods that allow different programs to communicate with each other”?

1. Real time
2. AJAX
3. Static website
4. API

Answer 33

4. API

Question 34

The DOM is a … of the various objects in the HTML document.

Answer 34

model

Question 35

How DOM works?

Answer 35

For every html element a model is created and called “object model”. These object models are presented as a tree structure where each node is an object model.