Pre-Computer Skills
Internet
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General Concepts
• Internet
A system of connected computers that allows
your computer to exchange data, messages and
files with any of the millions of other connected
computers.
• World Wide Web (www)
A collection of Web pages and related resources
which are linked together across the Internet
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General Concepts
• Intranet
A private network that is contained within an
enterprise, and used to share company
information among employees.
• Extranet
A private network that uses Internet technology
to share part of business information with
suppliers, partners, customers or other
businesses.
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General Concepts
• Hyperlink
A piece of text that can perform an action when
the users clicks on it.
• Web Browsers
Are computer programs that allow people to
access information on the World Wide Web
(WWW), e.g. Microsoft Internet Explorer and
Netscape Navigator
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General Concepts
• Web Site
A computer storage area that contains one or
more Web pages.
• Home Page
The first Web page you see when you launch
Internet Explorer.
• Uniform Resource Location (URL)
A unique address given to every web page
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General Concepts
• Protocol
A set of instructions for transferring data
between computers over the network
• Site Map or Site Index
is similar to a table of contents in a book; it tells
you where you can find information by category.
• Internet Service Provider (ISP)
A company that offers their customers access to
the Internet
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General Concepts
• Hyper Text Markup Language (HTML)
A set of formatting commands that you place
around a text or pictures to create a Web page.
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Internet Connection
Services
There are different Internet connection
services, such as:
• Dial-UP Connection:
– Early days of the Internet
– Computer  Modem  Phone Line
– To connect, user should dial up the ISP.
– Disadvantages:
• Very slow
• To make a phone call, you should disconnect the
Internet.
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Internet Connection
Services
• BroadBand Connection:
– Permanent connection to the internet
– No need to disconnect to make a phone call
– Immediate access to your email
– Fast service
– Paid on monthly basis, not by seconds.
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Options for Internet Connection
• Phone Line
– Most common option
– Uses your phone line for connection
– It needs a computer, a modem, a phone and an
account with an ISP.
• The mobile phone
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Wireless Technology
Uses the existing cellular telephone networks
Available anywhere there is a cellular coverage
Portable and perfect for traveling
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Options for Internet Connection
• Satellite
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–
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Delivers the Internet via satellite dish
Speed quite high
Requires special equipment
High cost
• Wireless Hot Spots
– Wireless and high speed Internet connections
– Often provided in airports, hotels, cafes, shopping
centers and restaurants
– Free for web browsing, but no downloading permitted.
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Characteristics of BroadBand
• Fast connection to the Internet
– Rapid loading of web pages
– Fast downloading of files and attachments
– Ability to talk to others (audio and video
chatting) and attend video conferences at real
time
• An Always-On connection
– Available 24 hours
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Characteristics of BroadBand
• Flat Fee Payment
– Cost depends on the speed of the service you
require, and the amount of downloads and uploads
• Risk of Intruder Attack
– Your computer is in constant contact, which enable
hackers to invade your computer connection
– Anti-virus programs should be up-to-date
– Firewalls are need to prevent unauthorized external
users from accessing the system.
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Security Consideration
• Identification (‫)تحديد هوية المستخدم‬
– A User ID is used to logon to a computer or a
computer network. It uniquely identifies you to the
network
• Authorization (‫ التوثيق‬- ‫)اثبات هوية المستخدم‬
– A proof that the user is authorized, either a
signature or a password.
• Authentication (‫ التفويض‬- ‫)تحديد صالحيات المستخدم‬
– Specifies the privileges given to users to access
certain resources or data.
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Security Considerations –
Password Policies
• Passwords: are secret words or numbers
that must be keyed into a computer
system to gain access.
• To make a password more effective:
– Do not share it with others
– Change it regularly
– Choose your password from a combination of
letters and numbers that are difficult to be
guessed by others.
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Security Considerations
Data Security
• Data Security: is a system of safeguards
for protecting information technology
against disasters, system failure, or
unauthorized access that can result in
damage or loss.
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Security Considerations
Backups
• They are copies of all software, files and
information which you have in your
computer systems. You can use those
copies when the original copies are
damaged because of physical failure, user
errors, accidents or carelessness.
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Security Considerations
Firewall
• A Firewall, is a set of related programs
located at a network server that protects
the resources of a private network from
users from other networks
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Security Considerations
Viruses
• Viruses are software programs which are written
with the intention of causing inconvenience and
disruption or serious damage in a computer
system. Files on floppies can spread viruses
across a network or via email and the internet.
• There are several types of viruses, some targets
specific types of files, others targets the main
memory, and others effect the booting of the
computer system.
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Security Considerations
How can Viruses enter a computer
system
• Viruses hide on disks. When you access
the disk, the virus will infect your
computer. It then can spread from one
computer to another. When you connect to
Internet, you have to make sure that
AntiVirus programs are working and are
updated.
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Security Considerations
Indicators of Virus infection
• There are some indicators that show you
that your computer might be infected by a
virus, such as:
– When it runs slower than normal
– When it crashes and restarts every few
minutes
– It restarts on its own and then fails to run
normally
– When you see unusual error messages
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Security Considerations
Protection against viruses
• To protect your computer against viruses, do the
following:
– Use a high-quality anti-virus program such as
(Norton and McAfee), and be sure to update it
regularly
– Always scan your disks and files after using them
on other computers
– Always scan the files you download from the
Internet. The same applies to attachments
downloaded from e-mails
– Make back-up copies of important documents or
files and store them on separate disk
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Security Considerations
Illegal Access
• Illegal access to the computer information
includes copying, modification and locking
of the data on the single computer,
computer systems and networks. The
main object of the illegal access to the
computer information is reaching the
owner’s information and invading his or
her privacy right.
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Security Considerations
Illegal Access
• Illegal access may cause the following:
– The web site is deleted, modified or corrupted
– Corporate networks will end up experiencing
virus attacks
– You will receive email threats
– Your mail will become available to an
unauthorized party
– Others will own your private information
– Modifications or corruption of the data bases
and documents
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Security Considerations
Hacking
• Hackers are people who create or improve
programs and share them with fellow
hackers to gain unauthorized access to
computer systems.
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Security Considerations
Password Cracker
• Password Cracking: is the process of recovering
passwords from data that has been stored in a
computer system.
• A common approach is to repeatedly try to
guess the password.
• The purpose of password cracking:
– Help a user recover a forgotten password
– Gain unauthorized access to a system
– Check for easily cracked passwords (Used by
administrators)
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Security Considerations
Encryption and Decryption
• Encryption: is the conversion of data into a
form that cannot be easily understood by
unauthorized people.
• Decryption: is the process of converting
encrypted data back into its original form,
so it can be understood. In order to do
that, a correct decryption key is required.
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