What is the internet? What is the Web? How does it work?

• The Internet is just millions of computers linked together.

• Often the link is a wire, or it may be a satellite dish.

• We often use Internet and the Web to mean the same thing.

• The Internet is the physical network whereas the Web is all the web pages.

• Computers need rules to send and receive information. These rules are called protocols.

• There are different protocols for different tasks. Hypertext Transfer Protocol (HTTP) is the set of rules which tell computers how to send and receive web pages.

What is a browser?

• A browser is a program which allows you to read web pages.

• Below are some of the more popular browsers, though there are many, many more!

• The interesting thing about browsers is the way they interpret web scripts, that have slight discrepancies that are important to understand when developing content to ensure compatibility.

• Chrome seems to be the users sweetheart at the moment, however, with continued threats in terms of cyber attacks and growing concernes with how data is being gathered and used, browsers such as firefox are making astonoshing comebacks given their 'Safe' nature. That and Chrome has bloated out to be a heavyweight browser, losing the trait that allowed it to topple IE off the throne all those years ago!

• I dont wanna say it.....but I'm gonna...but let me stress....I dont wanna.....MS Edge really isnt a bad option as far as browsers go....

Browser Usage Statistics 2019

Final notes on browsers

• Browsers allow us to follow links from one page to the next.

• Some links are internal (the page which is linked to is stored in the same place as the page from which the link is made). Other links are external (the page linked to is stored somewhere else)

• Browsers do other things such as store the history of pages you have visited and keep a list of your favourite pages.

A web server is a powerful computer which stores web pages. There are millions of these on the Internet.

In order to make a web site available all the web pages and files must be uploaded to the web server.

URLs (Uniform Resource Locators)

A uniform resource locator is shortened to URL. A URL allows us to find any file on the Internet. (Below are a couple of YouTube videos that explain URL's further including their structure.)

How are computers found on the internet?

• Every computer on the Internet has its own number. This is so that messages can go to and from the right place.

• These numbers are called IP (Internet Protocol) addresses (E.g. - IPv4: 207.68.137.36 or IPv6: 2001:0db8:85a3:0000:0000:8a2e:0370:7334 )

Most people remember the names of Internet connections using URLs, not IP addresses. www.microsoft.com is a URL (Uniform Resource Locator).

DNS Domain Name Service is like a huge international telephone directory which translates between web addresses and IP addresses

The web server may also hold DNS tables which allow us to access a site using a domain name such as www.bbc.co.uk

Lets take a look at how this works in practice!

If you can, go to https://www.netacad.com/courses/packet-tracer and create a free account. By doing this, you enrol on a free and non-time commital course which introduced you to the basics of Packet Tracer. - I would really recommend you do this as you will learn a lot.

But first, you're probably saying..."Pump the breaks!, I dont even know what Packet Tracer is! Why would I download it!? Free or not!"

Well, Packet tracer is a network simulation tool built by Cisco. Cisco is an industry leader in computer networking. They develop, manufacture and sell networking hardware, software, telecommunications equipment and other high-technology services and products. They also offer a host of globally recognised qualifications that are a big deal in the computing world.

Packet tracer allows you to build and configure networks of any scale you want! I would like to show you how to build a small network and use IP addresses to send a packet of information between computers. This will give you the practice, and the understanding of how computer networks work, as well as give you some practical experience in a simulated environment.

SIDE NOTE: Should you not own the PC you are working on, please both check with the device owner that it is ok for you to download and install software and also check with the bill payer that it is suitable for you to download a file of approximately 200MB. This software will take approximately 500MB of storage space on your computer.

If you have managed to download Packet Tracer, please follow along with the tutorial below as this will help you understand IP Addressing and communication between computer systems.