OPERATION
... on computers
FROM
HUMAN LIVES TO MACHINES...
May be you need not treat the computer like a patient,well,
some times it contains a virus.. Oh!no!no! please wait,you need not pull
up an injection or start scribbling a prescription. Just relax, Engineers
will take care of it and its not your job. you might wonder how come Engineers
will eliminate the virus, then what are we Doctors for if not for treating
virus infections.
Well,computer is a machine it doesn't have life as precious as human beings
nor it does think on its own, but it can be your best servant,secretary,accountant,
postman, or even a slave etc etc...yes computer can be called as a slave
as the only way we can speak to it is by giving commands to it for its
works.command in computer vocabulary is the instruction given by the user
operating on the computer to make the computer to do the job for the person.
Then again, you have to give orders for each and every activity of its
work in a very precise manner otherwise they will disobey you, even might
write back most funny messages which will get on to your nerves and test
your blood pressure.
Please donot make any wild guesses that computer virus is a microscopic
organism that is not visible to human eye and may be on any part of the
computer and will spread to human beings if touched.no.sorry.
Right now, just keep in mind that virus is a software program that is nothing
but a set of instructions to make the computer get ill. one more thing
you need not wear gloves to touch a computer with virus.It spreads only
from computer to computer just like human virus only when the body fluids
are exchanged the virus spreads same way only when the data gets transferred
from computer to computer the virus infection starts.
You may ask why should we know about computers ,well a life was saved because
of the computer and its technology. A person traveling alone on a ship
suddenly became very sick and had to undergo an operation, but alas, he
was in the middle of the ocean and no one near in the vicinity but a computer
and a modem through which he can communicate with the outside world.
He used the computer to chat with the Doctor and the doctor gave him step
by step instructions and the person himself performed the operation on
him by himself and finally his life was saved. Miraculous it may sound
but it happened and it was possible since the doctor was a computer literate
and he know the usage of internet.
Hope this one incident would have medically touched your heart and you
would definitely bubble with enthusiasm to learn about computers just how
you were when learning your first lesson about human anatomy in medical
college.
So before going into virus and internet you have to know about the basic
components by which the computer is made up.After all you might have learnt
about the human body parts and its basic functions before you learnt about
how the brain transmits the signals through nervous system for the activities.
Like only a doctor can perform open heart surgery only a hard ware engineer
can open the computer body.so with out any necessity to open the computer
you can learn about their parts. A computer just like our human body has
a well defined physical structure and a brain from where the operations
are executed.
MONITOR
Firstly the most striking and visible part of computer
is its face which is called as monitor,we understand other person's communication
by looking at his facial expression and listening to the words the person
speaks. same way we understand computer only by looking its monitor which
is nothing but the screen and is technically called as VDU( visual display
unit). we apply make up to the face for better appearance, monitors for
better display performance can also be tuned according to its resolution
which is nothing but number of dots on the screen,the higher the resolution
better the picture.The images formed on the screen is handled by video
controller.The activity of reading the display memory and painting a new
picture is done 50 times a second.The monitor comes with many control knobs
to adjust the display for its brightness,contrast,vertical size and horizontal
size etc and also an on/off switch.
Human beings have different complexions that cannot be easily grouped as
there are so many but computer monitors can be categorized into two main
types.one is mono chrome monitor which can display black and white color
only just like our B/W TV and other is color monitor which can display
even 16 million shades of colors.
Talking about monitors you know what happens when radiation strikes human
eye continuosly,yes computer monitors transmit radiation that is harmful
to eye,so its advisable to put anti glare cover over the montor.people
who work with laser beams wear fiber glasses ,well that much precaution
is not needed but its better to choose a monitor that has very low radiation.
Now monitors come with mike which can listen to the sound and speakers
which can give out sound from the computer,these kind of monitors are called
as multimedia monitors and so the similarity between human face and monitor
is almost reached.but monitor is made up of thick fiber glass unlike our
soft skin face.
MICROPROCESSOR
Microprocessor or CPU(central processing unit) is
the brain of the computer is a single integrated circuit (IC)and commonly
called as chip (no wonder we named our magazine as CHIP) and the whole
processing of the computer like arithmetic and logical calculations are
done by it. The speed of the processor is measured in Mhz by a clock which
is a small chip made of quartz which calculates the speed of the chip just
like the thermometer measures the temperature of the body.The higher the
number faster the speed,Now the microprocessor giant INTEL has come up
with 500 Mhz and 750 Mhz and 1000 Mhz are in the making.
MEMORY
Our brain has numerous memory cells like wise computer
has specific types of memory namely RAM,ROM and cache.The combination of
all the three is called as primary storage which is used to store the data
until the central processing unit gets ready for processing.computer uses
binary system and its memory is organized internally as a collection of
bytes. 0 and 1 called a bit, 8 bits are called as a byte. 1024 bytes are
called as kilobyte(KB).1024 kilobytes are called as 1 megabyte(MB),1024
megabytes are called as 1 giga byte(GB).
While you are doing the surgery you keep the instruments like knife,needles,scissors
ready near you in a tray, same way RAM is used for keeping the programs
and their data while the computer is working with them.RAM is called as
random access memory.
You keep a table,lighting and instruments needed ready before the operation,the
same way before the start of the computer, ROM contains permanently recorded
instructions that are vital for starting up a computer. ROM does the basic
control and supervisory operations of the computer called as ROM BIOS (Random
Access Memory Basic Input Output Services)
While you are performing the operation your hands will be holding some
frequently used surgical tools,same way computer holds the very frequently
needed information for the processor in cache.
Apart from the tray and hands which hold the necessary instruments you
may have many more instruments stored in the shelves of your operating
theater or lab, same way computer has hard disks, magnetic tapes, floppy
disks which store the data as external source for the processor.
HARD DISK
Hard disk is a rigid aluminum sealed unit and its
capacities vary. A small hospital in a village will have a very small lab
space with some mandatory instruments,but big hospitals in metro cities
will have enormous lab space with all the modern equipments.same way the
capacity of hard disks depend on the capacity of storage of data.They vary
from 20 MB to 27 GB.
In 1980's hard disks came with capacity of 20 MB now they come with 2 GB
to 27GB.earlier even 20 MB hard disk was very costly and the people tried
to store the data in a very economical way.In those days, 'year' in the
date was mentioned with 2 digits to save the hard disk space and that has
led to the major Y2K problem the whole world is facing now.say you are
born in 1960 and your year of birth is stored in the computer as 60.In
1999 your age is 99-60 = 39, but in 2000 your age becomes according to
computer calculation 00-60 = -60.so your age according to the computer
will be -60.so right from a person's age to bank account interest, everything
will produce a wrong value and this is called Y2K problem .
FLOPPY DISK
Next type of storage devices are floppy disks which
helps in transferring data and also virus from computer to computer.They
are made up of flexible mylar plastic and for data transfer they have be
inserted inside the drive which holds them t connect it with the processor.
There are 2 types of floppy disks one is of 3 1/2 inch and the other is
5 1/4 inch, the storage capacity being 1.44MB and 1.2 MB respectively.In
all these devices data is stored in tracks.you can protect the floppy disk
from anyone writing on to it or altering its contents using its small write
protect tab.
BUS
The memory chips and the processor communicate using
set of wires which serve as a common carrier for signals which is a communication
channel and the entire setup is called as a Bus.They can pass signals between
them back and forth just like our blood vessels pump up the blood to various
parts of the body continuously.
MOTHER BOARD
Mother board is to computer what thorax and abdomen
is for human body. yes,this is the main body of the computer which is an
electronic board with embedded tiny chips and other components.All external
devices such as printer,modem,digitizer and scanner are connected to the
mother board.It's main components are normally microprocessor,memory,bus
and ports.Ports are standard interfaces that are used to connect Input
Output devices like mouse,printer and scanner to the computer.There are
two types namely serial port and parallel port.Serial port sends data bit
by bit after 8 bits are queued up, where as parallel port sends all the
8 bits of data simultaneously.
KEY BOARD
Keying in the data is the main mode for talking to
the computer.Keyboard is the output device.When you press a key the scan
code is transmitted and the computer translates that into action.Normally
keyboards come up with 101 keys which includes 12 function keys located
on the top edge.now a days key boards come up with 108 keys with one-touch
window and one touch web keys. Key board is just like a type writer,but
hard hitting the keys should be avoided as they are very soft unlike type
writer keys. doctors have found out frequent users of the keyboard and
the people who type very fast,develop nervous complexities with their fingers.Now
key boards even come with palm rest top to keep the palm on the same altitude
as the keyboard to minimize the difficulty in typing and hand strain.
MOUSE
Well this mouse doesn't spread plague or run fast
,instead it calmly rest on the little space allocated for it to rest,on
the mouse pad.It is used to point and select some options on the screen.It
has either two buttons or three buttons and each button's function can
be configured according to our need using the mouse software that comes
along with the mouse kit.We can move them by rolling them on the mouse
pad and the cursor on the screen moves according to the rolling movement
of the tiny ball at the bottom of the mouse.It is also used to draw pictures
using paint soft wares.
Other devices that are used like mouse are joystick which looks like a
gear box and is mainly used for playing games normally people handle it
very rough, and track ball which is physically just opposite to mouse as
the ball is on top in track ball and you have to tap the ball using your
finger for the movement of the cursor.One more instrument is a digitizer
which is used for accuracy, they are made up of two parts a tablet and
stylus. A tablet is a flat rectangular box that is the pointing area and
the stylus is the pointing device.In lap top computers which are portable
the pointing device is a small knob which is fixed in the middle of the
key board between the keys. In some cases it is a track ball or mini handsensitive
fiber glass on which if you move the finger and the cursor moves according
to it.
PRINTER
It is an output device, connected through a parallel
port.It is used to print whatever you see on the screen and whatever data
contents that are in the storage devices.You can get the outputs like medical
bills,reports etc. Now printers come up with 'print on anything' type.you
can print the data or image on the OHP sheet or even on a cloth.There are
three types printers namely dotmatrix,inkjet and laser.
Dot matrix printers give the output like the conventional type writter.It's
output is poor. A dot-matrix printer is a good choice for printing multiple
copy carbon forms. The impact of the print head is sufficient to transfer
the carbon to form's copies.Their print head contains a single row or several
rows of line needles,The protruding needles press the ink ribbon and mark
the paper with the letters as inkdots,they normally come in 9 pin and 24
pin versions.The printer's resolution relates to how closely the dots are
printed next to one another
Ink jet printers have made tremendous advances in recent years,they cost
little more than dot matrix printer,and they have the advantage of producing
near photo quality printout.inkjet printers use ink cartridges , the print
head draws ink from the cartridge and sprays it through a serious of vertically
aligned nozzles that produce fine drops of ink creating the characters.These
printers can be categorized according to their color capabilities,mono
printers with black ink cartridge print only in black color. Color printers
which use three basic color inks like Red, Green and Blue are programmed
to produce any shade of color by mixing the three basic colors.
Laser printers have revolutionized the market by their photo realism and
near typeset quality output also they are super fast compared to dot matrix
and ink jet printers. In these types the computer sends a page of information
to the printer and the printer stores that page in its memory,then the
image is transferred to a cylindrical drum,the drum turns through the toner
and the toner clings to the image on the drum. When the paper passes under
the drum,the printer fuses the toner onto the page and the printer ejects
the page with the image.
CD-ROM DRIVE
CD-ROM DRIVE is a multimedia component which is used
to play audio-cd and video-cd, their speed is measured in 1X to 24X, according
to the speed of the data transfer it does from the CD to the computer.A
CD-ROM is a circular disc and is categorized in to audi-cd,video-cd and
data-cd normally contains 650 MB storage space and they cannot be written
on and it's read olny.You can play a movie using video-cd and you can listen
to songs using audio-cd.Now interactive CD's on various health related
topics have been released like the 'THE WISDOM WITH IN' by doctor Deepak
Chopra which teaches the policies for Total well-being.
Now multimedia kit comes with a mike,speakers,CD-ROM drive,software and
remote control to activate the drive from a distance.you can do play,forward,rewind
even skip to a particular spot on the CD. As the data stored cannot be
erased,it is a very safe medium to keep your data,normally it guarantees
100 years for data reliability.you need a device called CD writer to write
onto the CD.you can also replicate a CD and now the replication is done
at a very low cost.Now DVD (Digital Video Disk)has come into play and they
have storage capacity in the range of MBs.They are played using DVD players
which are costly.VGA(Video Graphic Adaptor)cards are used for increasing
the performance of the video output.for better results now MPEG(Moving
Pictures Expert Group)cards are available through which you can view a
movie Video CD with as much clear picture quality as you get on TV.
CABINET
All parts of the computer except monitor,keyboard
and mouse are fitted in side a cabinet along with a power supply unit called
as SMPS(switch mode power supply) which gets the power from our power board
and feeds the power for the operation of the computer for it's safety as
direct supply of power is dangerous for computer parts. All the parts inside
the cabinet are inter connected using cable wires.
Just like how our human body parts are connected by nerves to transmit
the commands by brain,the computer parts are connected by cable wires with
the mother board to get the command from the processor for the actions
,even if a single cable is cut the particular operation will be halted.
Now Apple computers have come up with their latest model for it's iMac
range of computers, they have designed in such a way that the cabinet is
fitted inside the monitor which really gives a futuristic look.
MODEM
Gone are the days of waiting for
the postman or writing letters and posting them as E-mail has come to stay.
E-mail is nothing but electronic mail. Also ISD and STD telephone bills
are replaced by Internet and E-mail almost up to ninety percent.Thanks
to a small instrument and it's mode of sure and easy communication
- modem. The two types of modems are internal and external modem. Internal
modem is just an electronic card which can be inserted in a slot
on the mother board and it doesn't need additional power supply, where
as the external modem needs additional power supply and looks like a small
box which is usually kept outside the cabinet.
Data is not sent through the
modem as digital data ( 0 and 1) but is modulated into a signal known as
carrier signal.The name mo-dem is formed from mo-dulation and dem-odulation.
Modem's speed is calculated in terms of bps which means bits per
second. The data travel along phone lines.Transmission through cable is
yet to properly hit the Indian market.You can also send and receive fax
using a PC through modem by a fax software and for the general function
of modem you need a communication software that comes along with modem.
Also there is remote control software
, it helps you to link your computer with a remote computer by a normal
telecommunication connection and then you can operate the remote computer
as if it was the computer in front of you, this is a remarkable facility
as you can operate the computer at hospital through your computer at home.
Through an Internet Service Provider
of your region you can connect your PC over to internet and enjoy e-mail,on-line
chatting,create e-groups with other doctors and even give consultation
to your patients by creating a web site for you and posting forms through
which patients can submit their nature of complaints that will get accumulated
on to your database for you to reply at your own convenience through e-mail.
Microprocessor Hard
Disk Mouse
Floppy Disk
Modem Monitor
Cabinet Printer
CD-ROM
BUS