System Software –
Utility Programs and
Translators
Describe the purpose and use of common utility programs for computers
security (anti-virus, spyware protection and firewalls), disk organisation
(formatting, file transfer and defragmentation), and system maintenance
(system information and diagnosis, system clean up tools and automatic
updating)
Utilities
• Technically the OS is the software that controls and manages
the computer system, but most OS’s also include programs
called UTILITIES.
• These are not essential for the computer to work, but they
either, make it easy for the user to use it in some way or
provide housekeeping functionality.
Main Categorises
1.
2.
3.
Security utilities that keep your computer safe from hackers
and viruses,
Disk organisation utilities that help organise your files into
folder,
Maintenance utilities that tidy up the disk
Security Utilities
This is about keep the computer safe from hazards.
This hazards could be:
• Viruses,
• Hackers
• Spyware
But keep this is perspective, as the most dangeours thing to a
computer is the user, as they are accidentally delete files or put
tem in the wrong place!
Anti-Virus Software
• A computer virus is a software program that is designed to
copy itself over and over again and to attach itself to other
programs.
• Viruses do not damage the computer hardware. They affect
the data and programs stored on the computer.
• They can cause an immense amount of time wasting and
financial loss for people and businesses. For example, the
"Melissa" virus was so effective in spreading itself that many
huge corporations had to shut down their email systems until
the virus could be contained.
• The operating system tries to make sure that data is not
corrupted by viruses. In order to do this, anti virus software is
used.
Anti-Virus
There are a number of anti-virus programs available for wiping out viruses for example
• Norton,
• McAfee,
• Sophos and
• AVG.
The anti-virus software contains a database of known viruses. Every time a file is opened, the
anti-virus utility checks the content, looking for hidden viruses against its database.
When the utility recognises a virus pattern, it will alert the user, and ask them whether they
want to remove the virus and clean the system, or whether they simply want to 'quarantine'
the virus.
New and more damaging viruses are being written all the time and so to keep up with these
new threats, the anti-virus companies provide constant updates to their software. Normally,
you log on to the internet and the software will update itself either automatically or after a
certain period set by you.
There is usually a small annual fee involved for this service, but it is a small price to pay for
peace of mind.
Spyware
Spyware is a software program, that once installed on your computer, can monitor
and collect personal information about your web surfing habits and the web pages
that you visit.
You are usually unaware that your machine has been infected by spyware and it can
sit in the background, collecting information about you and then transmitting it
back to the author of the spyware - often advertisers who want to know what you
are interested in and what adverts you click on.
Spyware may be installed without your knowledge by downloading some
shareware or other software that seems to do something useful e.g. a free game
or utility.
Whilst spyware is normally harmless, it can interfere with your control of the
computer in other ways. It can install additional software which redirects the web
browser to sites that it wants you to visit. It can also change the computer settings
which can result in slow connect speeds and it can prevent you from accessing
secure internet services.
Spyware – Key-loggers
Key loggers are another form of spyware, but they are not
so harmless. The purpose of a key logger is to monitor and
store a record of every keystroke made on the computer.
This data may then be sent to a remote server without your
knowledge. It is specifically looking for user names and
passwords used for things such as bank accounts, credit
card numbers etc.
Computer security software normally includes an antispyware section to help detect these malicious programs.
You need regularly scan your system for spyware and key
loggers and remove them if they are found.
Firewalls
A firewall is a utility program (or it can also be a hardware device) that
filters the information coming through the Internet connection into your
personal computer or into a company's network.
Its main aim is to try to stop any attempts by intruders to enter your system
through the internet connection.
It is set up to allow mainly one way access, i.e. you can go out onto the
Internet and access pages, but it checks every data packet that either enters
or leaves the computer against a set of rules.
If the data coming back is from an unauthorised source then it is blocked.
More complicated firewalls allow you to alter the rules.
You may have heard people saying, 'I can't get on that site at school
because it's been blocked'; that is the firewall in action.
All networks and indeed all home PCs should have an active firewall.
Disk Organisation
Every 3-6 months you should be “TIDYING” your hard disk.
This could be:
• Formatting
• Folder structures and moving files
• Defragging
Disk Formatting
Before a hard disk can be used, it needs to be prepared so that it will be able to store files and
applications.
Disk formatting is the initial part of the process for preparing a hard disk or other storage
medium for its first use.
FAT32 (file Allocation Table) increases the number of bits used to address clusters and also
reduces the size of each cluster. The result is that it can support larger disks (up to 2 terabytes)
and better storage efficiency (less slack space).
NTFS (New Technology File System) is a proprietary file system developed by Microsoft
Corporation for its Windows line of operating systems, beginning with Windows NT 3.1 and
Windows 2000, including Windows XP, Windows Server 2003, and all their successors to date.
NTFS supersedes the FAT file system as the preferred file system for Microsoft's Windows
operating systems. NTFS has several technical improvements over FAT
Mac OS Extended (Journaled) is also HFS+, but it has an extra mechanism that avoids
corruption of the file system when something bad happens, such as loss of power during a
write operation.
Partitions
As part of the disk formatting procedure, 'partitions' are created.
These are what you or I know as 'drives'. A disk might be
partitioned into multiple drives, for example, C:, D:, E:, S: etc.
Each partition or drive will have a different purpose.
• C: might be where the application files are stored.
• D: might be the drive used for external storage media, e.g.
USB stick,
• S: might be the shared drive on your school network.
The disk formatting also includes setting up an empty file system
which will allow folders and files to be created and deleted in the
normal way.
These tasks are carried out by a disk formatting utility.
File Transfer
One of the basic things you need to be able to do is to create, move, copy and delete files on the
computer system.
If you were to use a command line user interface to do this, you would type the instructions directly
into MSDOS. For example, the command for copying a file looks like C:> copy myfile.txt newfile.txt
This is actually quite a lot of work in terms of typing correctly and unless you are an expert at using
command line interfaces, you probably wouldn't know how to write the instructions required.
A much more convenient way, and the way that most of us probably do it, is to use a graphical file
handling utility such as 'Explorer' in Windows.
This utility shows files graphically as icons within folders along with the file name other details such as
file size, file type and date modified can also be viewed.
You can manipulate the files in a number of ways:
• drag and drop using the mouse will allow you to move a file
• right clicking on a file and choosing an option from a menu e.g. move, copy, cut, delete
• highlighting the file and choosing an option from the menu bar on Explorer's window
• highlighing a file and using a keyboard shortcut such as Ctrl-C, Ctrl-V
Defragmentation
After a while your computer begins to
run more slowly. One reason for this is
because over time, files and folders on
the hard disk become fragmented or
scattered.
When you try to run an application, a
large number of files often need to be
accessed.
Instead of always being stored next to
each other on the hard disk platters, the
files can become scattered, sometimes
ending up at opposite ends of the disk.
The hard disk then has a lot of work to
do in order to locate everything that is
needed to run your application.
Very occasionally, the files can become
so fragmented that it might cause a
program to stop running.
• To overcome this problem, it is a good idea to regularly
defragment or "defrag" your hard disk.
• All computer systems have a defragmenter utility preinstalled. When it is run, it will reorganise the hard drive by
putting pieces of related data back together so that files are
stored contiguously (next to each other). This may also free up
more space on the hard disk.
• Defragging a disk can take many hours, especially if you have a
lot of applications installed and a lot of files saved on the hard
disk.
System information and
diagnosis
System Information
The operating system keeps a record of all the hardware and details of the
operating system such as make, clock speed, number of processors, version
numbers and so on.
It does this by using a 'system information' utility.
This is very useful for people when they need to know the details of the system,
perhaps to see if an application they are considering getting will be compatible.
Diagnostics
These utilities will test the system to see if there are any problems. For example
an utility called 'chkdisk' or ‘Ccleaner’ on a windows system will run a number
of tests on the hard disk to see if it working properly.
System Clean-up tools
Over time some parts of the system become cluttered with old
installation details, temporary files, dead shortcuts and so on.
A good disk cleanup tool will search for and delete files which are
no longer needed. One of the benefits of doing this is that large
amounts of storage space is released. This can then be used for
other programs or files.
A system cleanup tool will search the computer for settings which
are no longer needed or for programs which are slowing down
the computer. Running this utility regularly can help to improve
the performance and speed up the boot-up time so that the
computer starts up much faster.
Automatic Updating
This is a very important utility that automatically searches the internet
for updated versions or patches for critical software such as the
operating system or the web browser.
If an update is found, it will be automatically downloaded and installed
and you will be prompted to restart your machine in order to apply the
patch.
Automatic updates help to ensure that your system is protected from
possible threats or security loopholes that could be exploited by
malicious programs or people in order to gain access to your system.
Automatic updates can also be applied to fix any known software bugs
in the system.