Computers 💻 | Welcome to the Internet! | 5.1

Question 1

Define internet

Answer 1

The world-wide interconnection of networks

Question 2

Define the World Wide Web

(WWW)

Answer 2

A massive collecion of webpages based on http and https

Question 3

What is the difference between the WWW and the internet?

Answer 3

The internet is the infrastructure, which is the connection of many networks. The WWW is a collection of multimedia webpages and other information on webpages.

Question 4

What is the difference between the WWW and the internet?

Answer 4

The internet is the infrastructure, which is the connection of many networks. The WWW is a collection of multimedia webpages and other information on webpages. delete later

Question 5

What does TCP stand for?

Answer 5

Transmission protocols

Question 6

What does IP stand for?

Answer 6

Internet Protocols

Question 7

How are https protocols written?

Answer 7

Using hypertext markup language (HTML)

Question 8

Web resources are accessed by __

Answer 8

Web browsers

Question 9

Define URL

Answer 9

A text-based address for a web page

Question 10

Define web broswer

Answer 10

Software that connects to a domain name server (DNS) to locate IP addresses; a browser interprets HTML web pages sent to a user’s computer so that the user can read documents and watch multimedia

Question 11

Define HTML

Answer 11

The language used to design, display and formal web pages, and to write http(s) protocols

Question 12

What does HTML stand for?

Answer 12

Hypertext mark-up language

Question 13

What does URL stand for?

Answer 13

Uniform Resource Locator

Question 14

What can a URL contain?

Answer 14

• Protocol
• Domain host
• Domain name
• Domain type
• Web page/file name

Question 15

What is the format of a URL?

Answer 15

protocol://websiteaddress/path/filename

Question 16

What does the website address contain?

Answer 16

• Domain host (www)
• Domain name (site name)
• Domain type (.com, .org, etc)
• Sometimes, country code (.uk, .de, etc)

Question 17

What does HTTP stand for?

Answer 17

Hypertext transfer protocol

Question 18

Define HTTP

Answer 18

A set of rules that must be obeyed when transferring files over the internet.

Question 19

Define HTTPS

Answer 19

Hypertext transfer protocol secure - http with extra security, such as SSL, applied

Question 20

In what situation does the protocol change from http to https?

Answer 20

When some form of security such as SSL or TLS is used

Question 21

List the functions of a web browser

Answer 21

• Convert HTML code
• Display web pages
• Check if a website is secure
• Request web pages from a web server
• Send URL/domain name
• Runs active script
• Store history/favourites/bookmarks
• Create tabs

Question 22

What is the main purpose of a web browser?

Answer 22

To render HTML and display web pages

Question 23

Define Domain Name Server (DNS)

Answer 23

A server that looks up domain names for websites in order to find the IP addresses that a computer needs to locate the web servers

Question 24

Explain the process of how a web page is located and sent back to the use, in the case where the IP address is not found in the first DNS server

Answer 24

1. User opens their browser and types in the URL. The browser asks the DNS server (1) for the IP address of the website
2. If the DNS server (1) can’t find the URL in its database or chache, it sends out a request to a DNS server (2)
3. The DNS (2) server finds the URL so it can map it to the IP address, sending it back to the DNS server (1), which then puts the IP address and its associated URL back into its cache or database
4. The IP address is sent back to the user’s computer
5. The computer now sets up a communication with the website server and the required pages are downloaded

Question 25

Explain what a DNS server does if it cannot find the matching URL for the IP address in its database

Answer 25

In this case, the DNS server sends out a request for a second DNS server to find the URL. This server maps the URL to the IP address, sends it back to the first DNS server, which sends it back to the user's computer

Question 26

In what two ways can a DNS server store URLs and IP address?

Answer 26

- Using a database of URLs and matching IP addresses - Using its cache

Question 27

Define *cookies*

Answer 27

A text file sent from a website to a user's browser; used to remember user preferences each time they enter the website

Question 28

What type of file is a cookie?

Answer 28

A *text file*

Question 29

What are the two types of cookies?

Answer 29

Session cookies and Persistent cookies

Question 30

Define session cookie

Answer 30

A cookie that is stored temporarily on a computer; it is deleted when the browser is closed or the website session ends

Question 31

Define persistent cookie

Answer 31

A cookie that is stored on the user's hard drive and only deleted when the expiry date is reached or the cookie is deleted by the user

Question 32

Define virtual shopping basket

Answer 32

An area of memory in a website where items a items a user wishes to purchase are temporarily stoed; items remain in the basket until payment is made or the session has ended

Question 33

Where are session cookies stored?

Answer 33

In the RAM or temporary memory

Question 34

Where are persistent cookies stored?

Answer 34

In the hard drive

Question 35

What type of cookies are used in virtual shopping baskets?

Answer 35

Session cookies

Question 36

How long do persistent cookies last?

Answer 36

Till the expiration date or user deletion

Question 37

Why are persistent cookies efficient at carrying data from one website to another?

Answer 37

It removes the need for massive amounts of user data to be stored on the web server itself

Question 38

What are the uses of persistent cookies?

Answer 38

- Allows the website to remember users' passwords, email addresses, and invoice details, so they don't have to insert all this information every time they visit - Serve as memory, so the website can recognise the user each visit - Save users' items in a virutal shopping basket/cart - Track internet habits and users' website history or favorites for advertising - Store users' preferences

Question 39

Define digital currency

Answer 39

Currency that exists in electronic form only, with no physical form - essentially data on a database

Question 40

What has the development of digital currency enabled?

Answer 40

- Banking online or on a smartphone app - The online sending of money

Question 41

How does a centralised digital currency sytem work?

Answer 41

The sender/buyer and reciever each may have their own bank they use. When money is transferred, the bank sends it to the central bank, which then transmits it to the second bank, and to the reciever

Question 42

What is the drawback of centralisation?

Answer 42

Issues maintaining confidentiality and security.

Question 43

Define cryptocurrency

Answer 43

A form of digital currency that uses a chain of decentralised computers to control and monitor transactions

Question 44

Define cryptography

Answer 44

The protection of data/information by use of coding; usually involving encryption and decryption

Question 45

What are the benefits of cryptocurrency compared to traditional banking?

Answer 45

- Traditional digital currencies are regulated by central banks and governments - making exchange rates influenced by state control. Cryptocurrency rules are uninfluenced by this and decided on by the community. - Cryptocurrency transactions are publically available, so all transactions are monitored and tracked - Cryptocurrency uses the more secure blockchain system

Question 46

Define blockchain

Answer 46

A blockchain is a digital ledger, that is a time-stamped series of records that cannot be altered, due to using a number of interconnected computers.

Question 47

Since blockchaining doesn't involve a centralised database, where is transaction data stored?

Answer 47

On **all** computers in the blockchain network

Question 48

In what areas is blockchain used?

Answer 48

- Cryptocurrency - Smart contracts - Research - Politics - Education

Question 49

Define *timestamp* | when it comes to blockchain

Answer 49

A digital record of the time and data that a data block is created in blockchain networks

Question 50

What does a single block in a blockchain contain?

Answer 50

- Data - Hash value - Previous hash value

Question 51

What *data* is often found in a *block*?

Answer 51

Name of sender and recipient, amount of money, and so on

Question 52

What is the hash value of a block in a *blockchain*?

Answer 52

A unique value generated by an algorithm which acts as a fingerprint

Question 53

What is the purpose of the previous hash value in a blockchain?

Answer 53

To point back to a previous block in the chain

Question 54

What is the *genesis block*?

Answer 54

The first block in a blockhain that doesn't point to any previous block

Question 55

How does a blockchain prevent tampering?

Answer 55

If the data in one block is changed, the data in further blocks will be invalid as the chain is broken

Question 56

Define *proof-of-work*

Answer 56

The algorithm used in blockchain networks to confirm a transaction and to produce new blocks to add to the chain; special users called miners complete and monitor transactions on the network for a reward

Question 57

What is the purpose of *proof of work*?

Answer 57

To make sure the process of creating new blocks is slowed down so that a new string of blocks cannot be quickly created