Transcript INTRODUCTION TO THE INTERNET AND EMAIL

INTRODUCTION TO THE
INTERNET AND EMAIL
CAIT
Introduction
• The internet & the WWW are household words today
• have redefined how people think & do business
• Despite their popularity, many people cannot answer
some most basic questions
o what makes up the internet
oIs it the same thing as the WWW
oHow did the internet begin & where is it heading
oHow can the internet be used to find specific
information
• This module addresses these questions and more
Evolution of the internet
• The internet is a worldwide collection of separate , but
interconnected networks
• A network is the interconnection of 2 or more devices for the
purpose of sharing resources.
• The internet (these interconnected networks) is accessed daily by
millions of people using a variety of devices to obtain information,
disseminate information, access entertainment or communicate
with others
• The US Department of Defense Advanced Research Projects
Agency (ARPA) created ARPANET in 1967
Evolution of the internet con’t
Objectives of the ARPANET
• To create a computer network that would allow researchers located in
different places to communicate with each other
• Build a computer network capable of sending or receiving data over a
variety of paths to ensure that network communication could continue
even if part of the network was destroyed – such as nuclear attack or by
a natural disaster
• Initially, ARPANET connected 4 supercomputers enabled researchers
and a few dozen academic institutions to communicate with each other
& with govt agencies
• As the project grew, students were also granted access to ARPANET as
hundreds of college and university networks were connected to it
Evolution of the internet con’t
• These networks consisted of a mixture of different
computers so, over the years, protocols were developed for
tying this mix of computers and networks together for
transferring data over the network and for ensuring data is
transferred intact
• Additional networks soon connected to ARPANET and this
internet- or network of networks– eventually evolved into
the present day internet.
*******Thus the root of the internet began with an
experimental project called ARPANET*********
The Internet
• The internet infrastructure can be used for a variety of purposes such as
•
•
•
•
•
•
•
Researching topics of interest
Exchanging e-mails
Participating in videoconferences
Downloading software, music & movies
Purchasing goods & services
Watching videos online
Sharing files with others
• Most of these services are available through the primary internet
resources– The WWW
The World Wide Web
• In its early years , the internet was used primarily by government, scientists,
educational institutions
• The internet went virtually unnoticed by the public & business community
for some years, because:
• It required a computer
• It was difficult to use
• As is the trend, computer & networking technology improved & new
application quickly followed
• In 1989, a researcher (Tim Berners-Lee) proposed the idea of WWW
• He envisioned the WWW as a way to organise information in the form of
pages linked together through selectable text or images (today’s hyperlinks)
on the screen
The World Wide Web
• The WWW became a popular way for researchers to provide written
information to others.
• In 1993, a group of professors & students at the University of Illinois National
centre for Supercomputing Applications (NCSA) released the Mosaic Web
browser
• A web Browser a software application used to locate, retrieve and also
display content on the WWW
• Computer program (such as Internet Explorer or Mozilla Firefox) that enables internet
users to access, navigate, and search World Wide ...
• Soon after, use of WWW began to increase dramatically because Mosaic’s
GUI made using the WWW both easier & more fun than before
• A growing number of today’s web based applications & services are referred
to as Web 2.0 applications
The World Wide Web con’t
• Web 2.0 is a term coined in 2004 that refers to a second generation of
internet based services that focus on web applications that facilitate online
collaboration , interoperability, user centred design and interactive
information sharing such as wikis, community database generation and photo
sharing
• Some Web 2.0 applications include
• Social networking sites
• Blogs
• wikis
• Today most companies regard their use of the internet and the WWW as
indispensable competitive business tool
• & many individuals view the internet & the Web as a vital research ,
communication & entertainment tool
The World Wide Web con’t
• Thus WWW refers to a collection of documents called web pages- available
through the internet
• A group of web pages belonging to one individual or company is a website
• Web pages are stored on computers called web servers, that are continually
connected to the internet
A server is a computer that "serves" many different computers in a network by running
specialized software and storing information.
It is a computer that controls and provides access to resources
• Web pages are viewed using a web browser such as Chrome, Safari, Opera,
Firefox
Server and Clients
• For example:
• In order for your browser
to display a web page, it
requests the data from
the server where the
page is stored.
• The server processs the
request, then sends the
data to your browser,
where it is displayed.
WWW & the internet
• The internet is the physical network of computers all over the world.
• The World Wide Web is a virtual network of web sites connected by
hyperlinks (or "links").
• Web sites are stored on servers on the internet, so the World Wide
Web is a part of the internet.
Internet
World Wide Web
1969, though opening of the network to
Estimated year of Origin
Comprises
Governed by
Dependency
commercial interests began only in 1988
1993
Network of Computers, copper wires, fibre- Files, folders & documents stored in various
optic cables & wireless networks
computers
Internet Protocol
Hyper Text Transfer Protocol
This is the base, independent of the World Wide
It depends on Internet to work
Web
Nature
Hardware
Software
The Internet Community Today
• The internet community today consists of individual business & a variety of
organisations located throughout the world
• Virtually anyone with a computer or other web-enabled device can be part
of this community
• Most members of the internet community fall into one or more of the
following groups.
• Users
• People who use the internet to retrieve content or perform online activities
• Internet service Providers (ISPs)
• Business or other organisations that provide internet access to otherstypically for a fee
• Examples of ISPs
The Internet Community Today con’t
Internet content Providers
• The suppliers of the information that is available through the internet
• Can be commercial business, non profit org, educational institutional, individual &
more
Application Service Providers
• The companies that manage & distribute web based S/W services to customers
over the internet
• Common ASP applications for business include Office suites, collaboration &
communication S/W, accounting
Infrastructure companies
• The enterprises that own or operate the paths or “roadways” along which Internet
data travels such as the Internet backbone & the communication networks
connected to it
• Eg of companies are mobile phone operators, cable companies & satellite internet
providers
The Internet Community Today con’t
Hardware & software companies
• The organisation that make & distribute the products used with the internet &
internet activities
• For eg companies that create or sell S/W use inconjuction with the internet such as
web browsers, email programs, e-commerce & multimedia s/w & web development
tools
• As well as companies that make the h/w such as NICs, modems, cables, routers,
switches, servers, computers, mobile phones that use the internet
• Government
• Ruling bodies of countries that can pass laws limiting both the information made
available via web servers located in a particular country & the access individuals
residing in that country have to the internet.
• Eg: In France it is illegal to sell items or post online content related to racist groups
or activities
Key Internet Organisations
• Other organisations that are responsible for many aspects of the Internet
eg
• The Internet Society (ISOC)—provides leadership in addressing issues that
may impact the future of the internet
• It also oversees the groups responsible for internet infrastructure
standards, such as determining the protocols that can be used and how
internet addresses are addressed.
• Internet Corporation for Assigned Names & Numbers (ICANN) ---Which
coordinates activities related to the Internet’s naming system such as IP
address allocation & domain name management
• World Wide Web Consortium (W3C)- a group of over 450 organisation
dedicated to develop new protocols & specifications to promote the
evolution of the Web & to ensure its interoperability
Who owns the Internet?
• No one individual or business owns the internet & the WWW & no single person or
business is in charge
• Each network connected to the internet is privately owned & managed individually
by that network’s administrator
• & the primary infrastructure that makes up the internet backbone is typically owned
by communications companies such as telephone & cable companies
• The closest the internet comes to having a governing body is a group of
organisations including ISOC, ICANN & W3C that are involved with issues such as
establishing the protocols used on the internet, making recommendations for
changes & encouraging cooperation between & coordinating communication among
the networks connected to the internet
• Governments in each country have the power to regulate the content and use of the
internet within their borders– as allowed by their laws.
• However, governmental controls are harder due to the “bombproof” design of the
internet.
Uses of the internet:
• Instant Messaging (IM)
o Allows you to exchange real-time typed messages . (Googletalk, Yahoo! Messenger)
• Tweeting:
• Internet Telephony
o Is the original industry term for the process of placing telephone calls over the internet…today the
standard term is VoIP
• Web Conference
o Often used for meetings between individuals located in different geographical locations.
• Webinars/webcast
o Similar to web conference but
o a presentation, lecture, workshop or seminar (webinar)
o Which is more of a one-way communication (webcast)
• Social Networking Site
• Loosely defined as any site that creates a community of individuals who can communicate with
and/or share information with one another
Uses of the internet: Online writing
• Blog
• Is a web page that contains short, frequently updated entries in chronological order
typically as a means of expression or communication
• Online personal journal accessible to the public that is usually created & updated by
0ne individual
• Wiki
• A collaborative webpage that is designed to be edited and republished by a variety
of users
• More handy for group projects
• E-commerce
• Online financial transaction
• However, online fraud, identity theft is on the increase & therefore users should be
on the watchout
Getting Setup to use the Internet
• Typically involve the following decisions
i. Determining the type of device you will use to access the internet
• Computer, mobile phone
ii. Deciding which type of connection you want
•
•
•
•
•
Dial-up
Cable
DSL (digital Subscriber Line)
Broadband
Wi-Fi hotspot
iii. Selecting the Internet Service Provider (ISP) to use
Accessing the Internet
• To request a web page or other resources located on the internet, its internet
address, - a unique numeric or text based is used
• The most common types of Internet addresses are :
IP addresses,
domain names (to identify computers)
URLs (to identify web pages)
Email addresses (to identify people)
• IP addresses & their corresponding domain names are used to identify
computers available through the internet
• IP (Internet Protocol) addresses are numeric such as 207.46.197.32
• A computer that hosts information available through the internet, such as web
server hosting web pages usually has a unique text-based domain name, such
as microsoft.com that corresponds to that computer’s IP address to make it
easier for people to request web pages located on that computer
Accessing the Internet con’t
• IP addresses & domain names are unique-no 2 computers on the internet use
the exact same IP address or the exact same domain name.
• The web site can be accessed using either its domain name or its
corresponding IP addresses.
• When a web site is requested by its domain name, the corresponding IP
address is looked up using one of the Internet’s domain name system (DNS)
servers & then the appropriate web page is displayed.
• Domain names typically reflect the name of the individual or organisation
associated with that web site
• The different parts of a domain name are separated by a period
• The far right part of the domain name is called the TLD (Top Level Domain) &
identifies the type of organisation or its location.
Accessing the Internet con’t
• .com for business/commercial
• .edu for educational institutions
• .jp for web sites located in japan
• .fr for web sites located in france
• South Africa? Australia? Mozambique?
Accessing the Internet con’t
• Similar to the way an IP address or domain name uniquely identifies a computer on
the internet, a URL (uniform Resource Locator) uniquely specifies web page by
specifying the protocol –or standard being used to display the web page, the web
server hosting the web page, the name of any folders on the web server in which
the web page file is stored and the web page’s file name if needed
• The most common web page protocols are
• http (Hypertext Transfer Protocol (http://) for regular web pages or
• https (hypertext Transfer Protocol secure (https://) for secure web pages that can
safely be used to transmit sensitive information such as credit card numbers
EXAMPLE URL
• http://twitter.com/jobs/index.html
Structure of a Uniform Resource Locator s
pathname
protocol
http://www.chicagosymphony.org/civicconcerts/index.htm
Domain name
http => Hypertext Transfer Protocol
filename
Using your browser
• Starting your Internet Explorer/ Firefox
• The page that appears is called the homepage or start page
• To navigate to a new page for which you know the URL…
• Can then use the hyperlinks
• Favourites/ Bookmarks
Search Engines
• With billions of web pages on the World Wide Web, how can you find exactly
what you're looking for?
• By using a search engine.
• Search engines are specialized programs that help you find what you're looking
for on the Web.
• It is a program that can search the Web on a specific topic for you.
• All you have to do is type in one or more keywords, and the search engine will
look for matching web sites from all over the Web.
• There are numerous search engines out there, but the most popular ones are
Google, and Yahoo
Class Discussion
• As a student, think of about four ways in which the internet could make
your life easier or more rewarding.
2. EMAIL
Introduction
• To contact people using the internet , we often use their email
addresses.
• An email address consists of a username (an identifying name)
followed by the @ symbol, followed by the domain name for the
computer that will be handling that person’s email (called a mail
server)
• For example :[email protected]
E-mail cont’
• is the computerised version of writing a letter and mailing it from a
local post office
• Is one of the heavily used internet tool
• It relies on the use of addresses, which is made up of 2 parts
o The domain name and the user name
o Eg: joe @ Nissiancloverleaf.com
E-mail cont’
The email Message :
• Consists of message text, recipient address, address of sender
• Other information could be included providing information on:
o Subject of the message
o Date and time stamp
o Carbon copy
E-mail cont’
• E-mail server
o Transmits outgoing messages
o Stores incoming messages
• Simple Mail Transfer Protocol (SMTP) is the protocol used to send out email
messages.
• It works hand in hand with the POP ( Post Office Protocol)
E-mail cont’
• When someone sends you an email, its transferred over the internet
from one server to another using SMTP
• When the message finally arrives at your email server, you can
download it to your computer using an email client employing the
Post Office Protocol.
Creating an email account
Create and send an email message
• Cc
• Bcc
• Subject
• Message body
• Reply All
•
Working with Attachments
• An attachment is a file that you send with an email message
• The file content does not appear within the message body.
• Most email servers limit the size of the file you can attach/
Email Nettiquette
• No all caps
• No Flaming
• A flame is a personal insult communicated through the internet.
• No Late Night Emails
• Sign messages
• Meaningful information in the subject line to clearly indicate the contents of
the message
• Content of the message short and related to the topic in the subject line.. Be
brief
• Limit the size of the attachment
• Check spelling
• An email like any written document, reflects your ability to communicate clearly and
effectively- - an IMPORTANT skill in any personal, academic or professional endeavour
Challenges of the Internet
•?????
3. WEB DESIGN BASICS
The World Wide Web
The Web (World Wide Web) consists of information organized into Web pages
containing text and graphic images.
It contains hypertext links, or highlighted keywords and images that lead to
related information.
WWW is a subset of the computer system on the internet consisting of servers
that store documents .
It is built on top of the internet.
A collection of linked Web pages that has a common theme or focus is called a
Web site.
In order to access this data your computer needs to run software known as web
browser ( Most popular are internet explorere, Netscape, Mozilla Firefox)
Introduction
• What is a good website???
o It downloads quickly
o Easily understood layout
o Clear view of objectives
o Useful textual information
o Interesting to look at
o Leads to other useful resources
• However, websites are useless if nobody visits them
How can you maintain visitor’s interest to your website
• Updating information regularly
• Image of site must continually change
• Maintaining corporate identity
• Search engines help users locate resources
• Its important that web designers understand search engines and how to use them to the best
advantage.
Web design guidelines
• Have knowledge of HTML
• The design must take into account of :
• The objectives of the website
• Who the users are
• What information should be conveyed
Hypertext Markup Language (HTML)
To allow Web browser software to read them, the text must be
formatted according to a generally accepted standard.
The standard used on the web is Hypertext markup language
(HTML).
Basics of HTML
•
•
•
•
•
•
•
•
•
•
Stands for Hypertext Markup language
Is based on text and tags
Is interpreted by a browser
We use a simple text editor for learning HTML
File endings are .htm or .html
Start tags switches format on < >
End tags switches format off < />
For example <i> </i> this tag switches italics on and off
Tag names are not case sensitive
< i> is not the same as <i>
Hypertext Markup Language (HTML)
• HTML uses codes, or tags, to tell the Web browser software how to display the
text contained in the document.
• For example, a Web browser reading the following line of text:
<B> A Review of the Book<I>Wind Instruments of
the 18th
Century</I></B>
• recognizes the <B> and </B> tags as instructions to display the entire line of text
in bold and the <I> and </I> tags as instructions to display the text enclosed by
those tags in italics.
Questions?
THANK YOU!!!!!
THE END