The document discusses key aspects of how the internet works, including: - The internet connects millions of computers globally through wired and wireless links, allowing people to search for information, communicate, and be entertained. - Domain names provide human-friendly addresses for websites, while IP addresses are unique numeric identifiers for each device; domain names point to IP addresses. - Packet switching breaks data into packets that contain sender/receiver addresses and are routed independently and reassembled at their destination via the most efficient path. - Routers read packet addresses and direct traffic along the least busy route between networks to deliver packets to their destination quickly and efficiently.

1. The Internet
What is the internet?
The internet is a shortened version of ‘Inter-Network’,
the internet is a global computer network which is used
by millions of people everyday. The internet is the
largest computer network in the world, which connects
millions of computers together which are digitally linked
by cable, fibre or wireless links. The internet is not only
used for searching information, but for communication,
entertainment and interacting with others. A huge part
of the internet is the World Wide Web, which is made
up from huge amounts of individual web pages, it is a
system of internet servers which also support
documents made from HTML.

2. Domain name & IP addresses
A domain name is a label that is given to a website to identify it,
for example ‘www.google.com’. Every domain name is unique so
it can be identified, and only one person/business can own it. A
domain name is used to access a website. However an IP
address is a set of numbers, which computers use to identify
each other, it is a set of numbers which is unique to each
computer connected to the internet. A domain name points to
an IP address, so that users all over the web can view a
webpage. Both domain names and IP addresses are very similar
as they both act as addresses and are unique.

3. Data packets and packet switching
Packet switching is a method, which breaks data down into
small parts which are called packets, it then sends the data
across networks. Packet switching is used by networks to
send data across short or long distances. Each individual
packet contains address information about the computer
which is sending data and also the receiver of the
information. A router is used to transfer the data between
two destinations in the most efficient way. The IP address
and of a web server and the IP address of a computer being
used is stored in a packet, along with more important
information. A packet can be sent all around the world and
may be sent by satellites or even fibre optic cables which
are under the sea, which carry digital information over long
distances. (they are strands of glass as small as human hair)

4. Routers
Routers are devices which sends data from one network
to another. It sends data packets to their destination
intended in the quickest and most efficient way. Inside
of a router there is a micro-computer which holds
memory of all networks which it is connected to, and
how busy each path of a network is. Firstly a router
reads the address of the data packet which has been
sent, next it checks the available path which leads to
the selected destination, it then checks how busy the
paths are which leads to the destination, finally the
router sends the information to the destination by the
quickest route, which is the path which is least busy.

5. Sources:
http://www.bbc.co.uk/guides/z3tbgk7#z9yk87h
http://www.teach-ict.com/gcse_new/internet/internet_www/miniweb/index.htm
http://www.teach-ict.com/gcse_new/networks/hardware/miniweb/pg4.htm
http://www.princeton.edu/~achaney/tmve/wiki100k/docs/Packet_switching.html
http://www.teach-ict.com/technology_explained/packet_switching/packet_switching.html