Computers are powerful electronic devices that process data and produce outputs. They are important tools used in many fields like education, science, business, and government. Computers have revolutionized communications through the internet. Computer crimes like software piracy and computer viruses are major issues. Piracy hurts software developers while viruses can damage programs and steal data. Various protections try to prevent piracy while antivirus software helps detect and remove viruses to keep computers secure.
2. Importance of computer in different
fields
• what are computers?
• Some say that they are simple electronic devices that
accept inputs, process data and produce outputs.
Computers may be simple but they can be very
powerful. Computers have begun to meet the barrier
imposed by the speed of light in achieving higher
speeds.
3. Importance of computer in different
fields
• Education
• Science
• Communications
• Business
• Government
• etc
4. Importance of computer in different
fields
• Science
All branches of science, from astronomy to
zoology, depend on computers to further their
knowledge on increasing the life span of man. The
MRI, the PET, and other computer-aided machines
help doctors and scientists to better understand the
people’s medical needs.
5. Importance of computer in different
fields
• Communications
Do you know that computers have even transformed how you
communicate with each other through the advancements in
technology?
One of these advancements is the Internet. Who among us
does not know anything about the Internet? Perhaps, using
computers will never be complete without using the Internet.
This global network of networks have swept the lives of many
people as daily tasks become handier, communications more
convenient, and most of all, sources of information broader
and more accessible.
6. Importance of computer in different
fields
• Business
Computer has changed how we do business. Gone are
the days of labor-intensive and manual way of
inputting data through ink and paper. Now, with a
few taps of keys and a few clicks of the mouse, good
and productive business is on its way.
7. Importance of computer in different
fields
• Government
Government offices also depend on computers for its
basic needs. From simple letters to the more
complicated projects are now being produced through
the use of computers. Government agencies and their
databases are now interlinked, making it easier for the
agencies to monitor economic developments.
10. Computer Crime - Software Piracy
• Software piracy – the illegal copying of software programs – is
the biggest legal issue affecting the computer industry.
• Piracy is of greatest concern to developers of commercial
software, or programs that must be purchased before using.
• Piracy is less of a concern for shareware makers, whose
programs must be registered but not always purchased.
• Piracy is not a concern for freeware, which is software that can
be freely distributed by anyone.
11. Computer Crime - Protections from Piracy
Various forms of copy protection have been used to discourage
piracy, including:
• Installation diskettes that record the number of times the
software is installed.
• Hardware locks, without which the program cannot
function.
• Passwords, serial numbers, or other codes required for
installation.
12. Theft - Hardware and Software Theft
• As PCs become smaller – and as more people use laptop and
handheld computers – hardware theft is becoming a growing
problem.
• Software theft is also a major problem for companies, many of
which must purchase large quantities of expensive software
programs.
• To combat hardware and software theft, many companies are
locking hardware to desks and securing software in libraries,
granting access to employees only as needed.
14. Computer Viruses
A virus is a parasitic program that infects another program (the
host). Most viruses fall into the following categories:
Categories of Viruses
Boot sector viruses Self-encrypting viruses
Cluster viruses Self-changing viruses
File-infecting viruses Stealth viruses
Worms Macro viruses
Bombs Joke programs
Trojan Horses Bimodal viruses
Polymorphic viruses Bipartite viruses
Self-garbling viruses Multipartite viruses
E-mail viruses Macro viruses
15. Types of Viruses
• Trojan Horses
– appears as interesting program file but when installed it
allows intruders to access and read your files
• Worms
– virus that copies and multiplies itself by using
computer networks and security flaws
• E-mail Viruses
– use e-mail messages to spread which allow it to
automatically forward itself to thousands of people
16. Types of Viruses
• Boot Sector Virus
– Infects the boot or MBR of diskettes and hard drives through the
sharing of infected disks and pirated software applications
– Once your hard drive is infected all diskettes that you use in your
computer will be infected
• Program Virus
– Becomes active when the program file (usually with extensions
.BIN, .COM, .EXE, .OVL, .DRV) carrying the virus is opened
– It then makes copies of itself and will infect other programs on the
computer
• Multipartite Virus
– Hybrid of a Boot Sector and Program viruses
– It infects program files and when the infected program is active it will
affect the boot record
17. Types of Viruses
• Stealth Virus
– Disguises itself to prevent from being detected by antivirus software
– It alters its file size or conceals itself in memory
• Polymorphic Virus
– Act like a chameleon, changing its virus signature (binary pattern)
every time it multiples and infects a new file
• Macro Virus
– Programmed as a macro embedded in a document, usually found in
Microsoft Word and Excel
– Once it gets in to your computer, every document you produce will
become infected
– Relatively new type of virus and may slip by your antivirus software if
you don't have the most recent version installed
18. Computer Viruses - Preventing Infection
Viruses are spread in several ways. The most common are:
• Receiving an infected disk.
• Downloading an infected executable file from a network or the
Internet.
• Copying a document file that is infected with a macro virus.
To avoid viruses, you should:
• Treat all disks as though they are infected.
• Install an antivirus program and keep its virus definitions (database of
virus information) up to date.
• Run your antivirus program regularly.
