Introduction to computers II What is computer?

 Introduction of computer

Computer basically means a tool or machine which computes or performs calculations. It is a programmable electronic device that is designed to work with Information. The word computer is derived from the Latin term 'computare', this means to calculate or program on it. Computer cannot do anything without a program. Computer is designed to execute applications and provides a variety of solutions by combining integrated hardware and software components. It is an electronic device that accepts information (in the form of digitalized data) and manipulates them for some result, based on a program or sequence of instructions. Therefore, 

Computer is a general purpose programmable machine, commonly consisting of digital circuitry, which accepts (input data), stores, manipulates, and generates (output information) in accordance with instructions called a program. 

The computer as we know today had its beginning and credited with a 19the century English mathematician professor Charles Babbage of Cambridge University. He is considered as the father of computer science because he designed the Analytical Engine which was the basic framework and innovation of the modern computers of today. The analytical engine included the fundamental parts and principle concept of computer programming. 

Importance of computer

Computers paly important roles in various purposes as the most people continue to use it almost every day. It is becoming a fundamental need in our day to day regular activities. Computer is also a powerful instrument for work, entertainment, study, trade, communication, etc. It is also very much important in official use, health sector, teaching and learning, business, service delivery etc. In fact, its significance does not require any mention furthermore. Smart phones are the types of palmtop computers and majority of people rely on Smart phones these days. 

We can understand and analyze the importance of computer by seeing a revolution in offline and online business, online education, online trade, online communication and internet banking. To store, access, manipulate, calculate, analyze data and information we use hardware devices and software application. All our daily life activities are based on such online services and products. Computer changed our life few decades ago and now it is a necessity to use a computer in daily life to live. 

Merits of computer 

• Computers are now crucial in different organizations such as office, bank, airways, railways, shops, business, industry, schools, etc. 
• Computers have made our life easier and faster by helping us to do many hard works quickly and inexpensively that we can't do manually. 
• Computers help scientist  do their research in every subject and even send spacecraft to another planet. 
  
• Computers can manage huge databases and access any information through the internet. 
• Computers are useful tool for entertainment to watch movies, play games, listen music, create animation, make communication etc. 
• Computers have become a source of income for numerous individuals and companies. 

Demerits of computer 

• Computer destroys our social life and isolates people from one another. 
• Computer affects our eyesight due to radiation and generates backbone problem due to the regular use. 
• Too much time in front of computer distracts our mind and disturbs our study. 
• Many contents on website are very harmful for children and teenagers. 

Basic Functions of computer 

Basically, the computer accepts data (raw facts or symbols) and converts in to meaningful information by means of data processing. Even the most basic models of computers are compatible with software that can perform the following basic and common functions. They are: 

a) Data Input (Inserting data and instructions) 

Every computer is designed with data input mechanism which is the first function. It is an activity which allows transferring instructions into the computer via input devices such as mouse, keyboard, scanner etc. 

b) Data processing (Manipulation of instruction) 

Data processing is the core function of a computer. Processing involves manipulation of raw data into meaningful information. Usually, data is in raw form, and will thus undergo processing before dissemination for user consumptions. The Central Processing Unit (CPU) manipulates and controls data over the entire system. 

c) Data Output (Displaying information) 

When raw data has been manipulated by the processor, the outcome is meant as information which is beneficial to the user. The output devices like computer monitor, printer, speakers; CD drives etc. play the role of displaying the information processed by the computer system. 

d) Data Storage (saving data or information) 

A computer can store information internally and externally for temporary and permanent purpose on its hard drive, CDs or DVDs or even in the cloud devices. How much information we can store will depend on the computer type, operating system and memory. 

Characteristics of computer

The main characteristics of computer are as follows: 

High Speed 

Computer devices, nowadays works at an amazing speed that we can't even image of. It works as fast as it works using electric signals which run like light speed. Computers can do billions of calculations in one second. If the smallest unit of time for humans is a second, then for computers it is picosecond, millisecond, microsecond, nanoseconds etc. 

Accuracy 

The accuracy of a computer is very high. It can perform the calculations with zero error rates. Some errors may occur in computer, but they are mainly due to human fault. Computer is based on the Garbage In Garbage Out (GIGO). If wrong data is given as input then it will produce wrong result or information. 

Decision making 

The computer has capability to perform task and managing processing schedules when there are many jobs available and waiting own turns. The Operating system has capability to manage files, executing utilities software, and many others. The game, weather forecasting, weaponry systems, aviation's, space shuttles etc. are controlled by computer and the controlling actions are performed by its decision making capacity based on stored related database. 

Diligence 

A computer is free from tiredness, lack of concentration, fatigue, etc. It can work for hours without creating any error. If millions of calculations are to be performed, a computer will perform every calculation with the same accuracy. Due to this capability it overpowers human beings in routine type of work. 

Versatility 

Computers have the capacity to perform completely different type of work in various sectors. We may use the computer to prepare payroll slips, word processing, spreadsheet calculations etc. Likewise, in a next moment we may use it for inventory management or to prepare electricity bills, salary sheet calculations, etc.

Storage 

Computer comes with high storage facility to store almost any amount of data in it. Not only have that, most computers come with expandable storage facility along with external storage. Computer is so fast that it also takes unnoticeable time to find the data user need from this huge storage. 

Limitations of Computer 

A computer does not have common sense. It just does what we tell it to do. It will never experience human emotions or concepts. A computer cannot take place of human because computer is always dependent of human. Some of the limitations of computers are given below:

No self-Intelligence 

Computer does not have any intelligence of its own. It works according to the given instruction    only. It only does the things that human programs it to do.

No feeling

A computer cannot feel anything as human and cannot meet human in respect of relations. It does not have feelings or emotion, taste, knowledge and experience. It does not distinguish between users.

No learning Power

Computer has no learning power. Once we give instructions to a  computer how to perform a task , it cannot perform the same task if we do not give it any instructions for the next time.

Dependency 

Computer can do a task only if it can be expressed in a series of finite steps leading to the completion of the task. It does not have perception . It cannot draw a conclusion without going through all intermediate steps.