1.1. Introduction to Computer
Concept and characteristics of computer
· The word “Computer” is derived from the Latin word “Computare” which means to calculate.
· Definition of Computer: - An electronic device which accepts raw data from users and processes it to give meaningful result and store the important data for future use is called Computer.
· 
Data: - The raw facts about anything are called data. Examples: Students data are name, address, class, roll no. etc.
· Instruction: - Instruction is specifying what must be done to the data.
For examples: SP = 1000 and CP = 700 are data.
To find profit (SP>CP) = SP-CP =1000-700= 300
· Information: - The processed data which gives meaningful result is called information. Example: 300 is profit.
· Hardware: - All the physical parts of the computer which we can touch and feel are called hardware.
Example: Mouse, Monitor, Keyboard etc
· Software: - A set of program written in a programming language for a computer to perform a particular task is called Software.
· Firmware: - The information written in ROM permanently by the manufactures is called firmware. Many computer manufacturing company make essential software, required for start up of the computer and available in ROM chips. The best example of firmware is BIOS (Basic input output system).
· Program: - A sequence of instructions that perform certain task is called Program.
· User: - The person who uses computer is called user.
· Peripheral: - The input, output and storage devices which can be connected to the system cabinet are called Computer Peripherals or peripheral devices. Examples: Printer, Scanner, Card reader etc.
# Characteristics of a computer:
a) Speed b) Accuracy c) Diligence d) Reliability
e) Versatility f) Automatic g) Storage Capacity
a) Speed: - Computers can perform billions of calculations within fractions of a second. Actually most modern computers perform a task in a Pico seconds. The processing speed of computer is measured in the unit of Hertz (Hz).
b) Accuracy: - Accuracy means correctness. Computer works on GIGO (Garbage input and garbage output) principal. It means the computer provides the correct result if the inputs are correct.
c) Diligence: - The computers never feel tired and bored to do a same task repeatedly. The computer can perform the same task with same speed and accuracy for a long time if it is provided the suitable environment and correct instruction.
d) Reliability: Computers are designed in such a way that their every individual part has a very high life span.
e) Versatile: - Modern computer perform various types of job efficiently. Same computer can be used in bank, office, school, cyber etc for doing different types of tasks. Some computer plays movies and music in it, other uses it as a server computer etc.
f) Automatic: Computer is an automatic machine because a task has started; a computer can proceed its own till its completion. A computer can be programmed to perform a number of tasks with the help of program.
g) Storage Capacity: - A computer has high storage capacity. It has data storage area called memory. Any data stored in the memory can be retried at any time and at very speed.
# Limitation/ Disadvantages of computer
a) Computer is an automatic device, even it requires operator to operate the computer.
b) Computer is very expensive in comparison to other electronic devices, so every people cannot afford it.
c) Computer cannot think itself to give decisions.
d) Computer requires technical person for maintenance if it does not work properly.
#Application of Computer
Although, the early computers were mainly used for mathematical calculations to predict impacts of bomb, path of artillery shells, calculate some other numerical values etc. By the development in technology, modern computers have played an important role in society. In modern days, computer are used in different fields, some of them are as follows:
a) Education
Computer has been used in education to help the students in their study and the teachers to organize and prepare their teaching materials and collect required information from the internet. Due to the availability of eBooks in CD, DVD and in internet, Computer has been very helpful and essential device for students and teacher for their better education.
b) Offices
Modern computers are very necessary and useful resources in office. In offices, computers are used in preparing the reports, letters, notice, salary sheet, income and expenditure reports etc. So that efficiency and work speed of the employees will be improved. Generally Microsoft Office and accounting package are used in an office to handle the daily works.
c) Health and Medical field
Computers have played a vital role in medical field as it has been used in hospital to help doctors, nurse and technicians to diagnose disease, getting information about patient, disease and drugs.
Similarly, many computerized equipment such as CT scan machine, eye testing machine and many computerized machines are used for experiment and disease diagnosis. Surgeon also uses the computerized device to get the information about the condition of patient.
d) Home
Nowadays computer are used in home to storing personal records, photos, videos, playing games, listening music, watching, watching movies etc. It can be used even to connect the internet and use services like email, chatting, online TV streaming, downloading songs and movies etc
e) Bank
Computerized technology has brought revolution in bank. Unlike in manual system, deposit and withdraw became quickly in computerized bank. A computer is also used to maintain ledger, to provide the online service to the customers who need services from their home, to transfer amount etc. For these purposes, there is a central computer called server. In bank, mostly in head offices, this stores all the necessary information centrally so that it can be accessed from any branch office of the bank. Because of this, a customer can get services from any branches of the bank.
Due to the computer with network facility, nowadays banks also provide ATM service to customers so that a customers with ATM card can perform a cash transaction immediately with the ATM machine at any time and from any place.
f) Industries
Computers have been used in industries for various purpose such as keeping the employees record, income and expenditure record, salary sheet, measurement and display of physical quality, quality control of production etc. The different tasks which are risky for human beings are being done by computerized robots in industries so that human life will not be at risk.
g) Science and technology
Since the invention of early computer, it has been a great aid for the mathematician and scientist for doing fast and correct calculation. Scientific and technological research work involves complex and massive calculations.
In many case, simulation is also required. Such massive calculation and simulation are not possible in paper or by hand calculations. Modern computers are most for scientific research for the analysis of data.
h) Recording and film studio
The modern computer can also be used for recording songs, movies and dialog. It is also used in film studies to do animation and movie production. It is used to make the movie more interesting, more popular and more attractive.
Nowadays, the music and songs can be recorded at different tracks, time and place. Similarly, movie editing also has been very easy due to the computerized system.
i) Weather forecasting
Weather forecasting is not an easy task as it is done after the analysis of the images, temperature, wind speed, humidity etc. of different places, which is sent by the satellite. The analysis of these large data is not possible without the use of computer. Computer analyzes the direction of the wind, cloud structure, past data and many other factors to forecast the weather. Due to the use of specific computers, we can see that BBC, CNN and other news channels predict the weather forecasting.
j) Reservation
By using the computer with internet facilities, the reservation for the air ticket, train ticket, bus ticket etc. becomes possible. It also stores information regarding passenger such as name, address, age, destination, data etc. Due to the credit card and debit card facility the passengers can reserve and purchase the tickets even from their own home computer.
k) Military
Since the past, computers have been used by armed force for testing and development of military devices like missiles, tanks and bullets etc. The pilot-less fighter planes can carry missile and drop at the pin-point area by the use of the computerized system. It also plays important role in military communication.
l) Communication
Due to the invention of the internet, modern computers are massively used for fast, reliable and cheap communication all around the world. Text, photo, animation, email, voice etc can be uncharged between two computers through the internet.
m) Library
We can use computer in library also to keep the records of books, magazines, reports, newspaper and other documents. We can keep also records of the library members with which books they have borrowed with detailed information.
Nowadays, many books are available in the digital format in the form of CD and DVD too. Similarly, many e-books are kept in the internet as e-library to read such e-books also, we need computers.
n) Desktop publishing house
Desktop publishing house is the place where the design and publication of different materials like book, magazine, journal etc take place. Before publishing these materials, if should be designed properly. Nowadays, there are many computerized software for desktop designing and publishing which makes it very easy and efficient. Some of the desktop publishing software as MS-Word, Adobe PageMaker and others, which is used to manipulated by computer system.
No comments:
Post a Comment