Rolland Merch M. Arriza
Mindanao State University – General Santos City
Back in the days when dinosaurs roamed the earth (in 1972), a guy named Ray
Tomlinson invented an email program to send messages across what was called
a distributed network.
shortened term for ―electronic
a system of receiving, sending,
and storing electronic messages
text messages that may contain
files, images, or other
attachments sent through a
network to a specified individual
or group of individuals
Some Email Providers:
Gmail, YahooMail, Outlook, Hot
Mail, GraphicMail, ClickMail,
Zoho Mail, AIM Mail, iCloud Mail,
Shortmail, and Inbox.
Figure 1: Different email providers
the first portion all e-mail
addresses is the
alias, user, group, or department
of a company
next, the @ (at sign) is used as
a divider in the e-mail address
and is always required for all
SMTP email addresses
Simple Mail Transfer Protocol
(SMTP) - communications
protocol that sends e-mail
messages from one server to
another over port 25.
last portion is the domain name
Figure 2: Email address
The World Wide Web is a huge collection of hypertext documents and
hypermedia. It has facilitated easy access to information over the Internet.
World Wide Web
Word Wide Web
Invented by Sir Timothy John
"Tim" Berners-Lee, a British
a system of Internet servers that
support specially formatted
documents. The documents are
formatted in a markup language
called HTML that supports links
to other documents, as well as
graphics, audio, and video files.
This means you can jump from
one document to another simply
by clicking on hot spots.
Internet is the means to access
this set of interlinked documents.
Figure 3: Timothy John Berners-Lee
Word Wide Web
The network of web servers
serves as the backbone of the
World Wide Web. The Hypertext
Transfer Protocol (HTTP) is
used to gain access to the web.
A web browser makes a request
for a particular web page to the
web server, which in turn
responds with the requested
web page and its contents.
It then displays the web page as
rendered by HTML or other web
languages used by the page.
Each resource on the web is
identified by a globally unique
Figure 4: Hypertext Transfer Protocol
Word Wide Web
Each web page has a unique
address, with the help of which a
browser accesses it. With the
help of the domain name
system, a hierarchical naming
system for computers and
resources participating in the
Internet, the URL is resolved into
an IP address.
Presence of hyperlinks, the
worldwide availability of content
and universal readership are
some of the striking features of
the World Wide Web. The
interlinked hypertext documents
form a web of information.
Figure 5: Hyperlink
Word Wide Web
Hyperlinks present on web
pages allow the web users to
choose their paths of traversal
across information on the web.
They provide an efficient cross-
referencing system and create a
non-linear form of text.
The information on the web is
available 24/7 across the globe.
It is updated in real time and
made accessible to web users
around the world. Except for
certain websites requiring user
login, all the other websites are
open to everyone.
Figure 6: Login interface
FTP, File Transfer Protocol, is a protocol through which internet users can upload
files from their computers to a website or download files from a website to their
File Transfer Protocol
File Transfer Protocol (FTP) is a
standard network protocol used
to transfer files from one host to
another host over a TCP-based
network, such as the Internet.
An FTP client is a program that
allows you to easily move files
from one computer to another.
In the case of creating a Web
site, this means that if you create
the pages for your site on your
computer, either using a text
editor or some other Web page
editor, then you will need to
move it to the server where your
site will be hosted. FTP is the
main way to do this.
Figure 7: File Transfer Protocol
TCP and IP are the two major
protocols that keep the internet
running smoothly. TCP manages
data transfer while IP directs
traffic to internet addresses. FTP
is an underling of TCP and
shuttles files back and forth
between FTP server and FTP
client. Because FTP requires
that two ports be open--the
server's and the client's--it
facilitates the exchange of large
files of information.
Figure 8: How FTP works
First, you as client make a TCP
control connection to the FTP
server's port 21 which will
remain open during the transfer
process. In response, the FTP
server opens a second
connection that is the data
connection from the server's port
20 to your computer.
Using the standard active mode
of FTP, your computer
communicates the port number
where it will stand by to receive
information from the controller
and the IP address--internet
location--from which or to which
you want files to be transferred.
Figure 8: FTP diagram
The first online chat system was called Talkomatic, created by Doug Brown and
David R. Woolley in 1974 on the PLATO System at the University of Illinois. It
offered several channels, each of which could accommodate up to five
people, with messages appearing on all users' screens character-by-character
as they were typed.
may refer to any kind of
communication over the Internet
that offers a real-time
transmission of text messages
from sender to receiver. Chat
messages are generally short in
order to enable other
participants to respond quickly.
Thereby, a feeling similar to a
spoken conversation is created,
which distinguishes chatting
from other text-based online
communication forms such as
Internet forums and email.
Figure 10: Chat presented in a Bubble
Online chat may address point-
to-point communications as well
as multicast communications
from one sender to many
receivers and voice and video
chat, or may be a feature of a
web conferencing service.
Online chat in a less stringent
definition may be primarily any
direct text-based or video-based
(webcams), one-on-one chat or
one-to-many group chat
(formally also known as
conferencing), using tools such
as instant messengers, Internet
Relay Chat (IRC), talkers and
Figure 11: Video chat
Major search engines such as Google, Yahoo (which uses Google),
AltaVista, and Lycos index the content of a large portion of the Web and
provide results that can run for pages - and consequently overwhelm the
A web search engine is a
software system that is designed
to search for information on the
World Wide Web.
The search results are generally
presented in a line of results
often referred to as search
engine results pages (SERPs).
The information may be a
specialist in web pages, images,
information and other types of
files. Some search engines also
mine data available in databases
or open directories.
Figure 12: Major web search engines
It is a set of programs that
Spider (or crawler) that goes to
every page or representative
pages on every Web site that
wants to be searchable and
reads it, using hypertext links on
each page to discover and read
a site's other pages
A program that creates a huge
index (sometimes called a
"catalog") from the pages that
have been read
A program that receives your
search request, compares it to
the entries in the index, and
returns results to you Figure 13: Spider (web crawler)
Web search engines work by
storing information about many
web pages, which they retrieve
from the page's HTML. These
pages are retrieved by a Web
crawler (sometimes also known
as a spider) — an automated
Web browser which follows
every link on the site.
The contents of each page are
then analyzed to determine how
it should be indexed (for
example, words can be
extracted from the titles, page
content, headings, or special
fields called meta tags). Figure 14: Spider (web crawler)
When a user enters a query into a
search engine (typically by using
keywords), the engine examines
its index and provides a listing of
best-matching web pages
according to its criteria, usually
with a short summary containing
the document's title and
sometimes parts of the text.
Most search engines support the
use of the boolean operators AND,
OR and NOT to further specify the
search query. Boolean operators
are for literal searches that allow
the user to refine and extend the
terms of the search. The engine
looks for the words or phrases
exactly as entered.
Figure 15: Google search query
The usefulness of a search engine
depends on the relevance of the
result set it gives back. While there
may be millions of web pages that
include a particular word or
phrase, some pages may be more
relevant, popular, or authoritative
Most search engines employ
methods to rank the results to
provide the "best" results first.
How a search engine decides
which pages are the best
matches, and what order the
results should be shown in, varies
widely from one engine to another.
Figure 16: Page rank system