5. the internet and its uses

is the infacture, a public network of computer systems across the globe.

Computers Servers Switches Routers Cables

the collection of resources that exist in the network ( inside the internet)

Web pages Documents Images Videos Music Emails

(URL): is a text-based address for a web page; it can contain the protocol, the domain name and the web page/file name

HTTP and HTTPS

uses request codes to send and recieve data

GET:GET request asks the web server to transmit a specific resource, such as a web page, to the user’s web browser. POST: adds new content DELETE: removes resources PUT: modifies source

Hypertext transfer protocol secure (HTTPS) is a secure method of sending data via the world wide web, and was invented to combat the glaring security risk of sending sensitive data via the HTTP protocol.

using a TLS a private key and pulic key are used for security

save important pages which user uses a lot- saves time

User history keeps a chronological ledger of each site visited. This is helpful if you cannot remember which website you viewed many weeks or months ago, or if you accidentally close a web browser window and would like to reopen the exact same page again.

allows use of many pages at the same time. his eases browsing between websites, and usually means less computer system resources are used

• Cookies are small files which store small amounts of data on our computer system, usually used to save our login details for certain websites, or provide advertising agencies with our data. • provides companies with some non-personal information about users, including some of their browsing history, in order to provide more personalised adverts.

reloading, adding tab, closing tab, going back, going forward etc

alows browing of web page without a link

1) user enters URL into the web browser adress bar 2) the URL points to a web page or resouce on WWW. 3) computer connectes to the internet communicate with each other using their IP adresses 4) the DNS server keeps a record of all the domains in existance and maps each of these into a IP adress- looks up domain names and replies request with IP adres 5) the web server will eaither allow or not acess to the source depending on the nature of the request 6) web server returning the resource to the web browser. This is usually raw HTML, which the web browser then translates into a readable format for the user.

HTTP cookies are small pieces of data that are stored on the users’ computer system, and are used by the web browser to retain information

• Saving personal details • Tracking user preferences • Holding items in a shopping cart • Storing login details

• provide long term storage for preferences. store login details etc. • stored in HDD

session cookie is stored temporarily in your computer, stored in ram. used for sensetive info. a request will be sent after every logging in and wont be saved

A digital currency is one that only exists electronically. has no physical attributes eg: bitcoin, ethereum, doge coin

• anonymous • anyone can access • no taking cut of transaction cannot be manipulates by large organizations • decentralizes

• uses lots of resouces to compute hashes • some currencies are not accepted widley • value tends to fluctuate over short and long term