Fundamentals of Computer Part - 1

Mentor for Bank Exams
Concept of Computer System:-
A computer is an advanced electronic device that takes raw data as input from the user and processes this data under the control of set of instructions (called program) and gives the result (output) and saves output for the future reference and usage.
C - Commonly; O - Oriented; M - Machine; P - Particularly; U - Used; T - for Trade; E - Education; R - and Research.

To know about the working of a computer, first need to understand various terms such as Data, Processing and Information. First of all, lets start with three basic terms:-
1. Data: Data is a collection of basic facts and figure without any sequence. This data is also called as raw data. When the data is collected as facts and figures, there is no meaning to it, at that time, for example, name of people, names of employees etc.
2. Processing: Processing is the set of instructions given by the user to the related data that was collected earlier to output meaningful information. The computer does the required processing by making the necessary calculations, comparisons and decisions.
3. Information: Information is the end point or the final output of any processed work. This meaningful output data is called information.
Characteristics of Computer:-
The major characteristics of computers are the following:
  • Speed: A powerful computer is capable of executing about 3 million calculations per second.
  • Accuracy: A computer’s accuracy is consistently high; if there are errors, they are due to errors in instructions given by the programmer.
  • Reliability: The output generated by the computer is very reliable as long as the data is reliable.
  • Memory/Storage Capacity: The computer can store large volumes of data and makes the retrieval of data an easy task.
  • Versatility: The computer can accomplish many different things. It can accept information through various input-output devices, perform arithmetic and logic operations, generate a variety of outputs in a variety of forms, etc.
  • Automation: Once the instructions are fed into computer it works automatically without any human intervention.
  • Diligence: A computer will never fail to perform its task due to distraction or laziness.
  • Convenience: Computers are usually easy to access, and allow people to find information easily that without a would be very difficult.
  • Flexibility: Computers can be used for entertainment, for business, by people who hold different ideals or who have varied goals. Almost anyone can use a computer, and computers can be used to assist with almost any goal.
Goals of Computers:-
1. Problem-solving techniques using the computer.
2. Analysis of complex problems and the synthesis of solutions .
3. Comprehension of modern software engineering principles.
4. A vast breadth and depth of knowledge in the discipline of computer science.
Types of computers:-
Computers range in size and capability. At one end of the scale are supercomputers, very large computers with thousands of linked microprocessors that perform extremely complex calculations. At the other end are tiny computers embedded in cars, TVs, stereo systems, calculators, and appliances. These computers are built to perform a limited number of tasks.
Desktop computers
Desktop computers are designed for use at a desk or table. They are typically larger and more powerful than other types of personal computers. Desktop computers are made up of separate components. The main component, called the system unit, is usually a rectangular case that sits on or underneath a desk. Other components, such as the monitor, mouse, and keyboard, connect to the system unit.
Laptops are lightweight mobile PCs with a thin screen. Laptops can operate on batteries, so you can take them anywhere. Unlike desktops, laptops combine the CPU, screen, and keyboard in a single case. The screen folds down onto the keyboard when not in use.
Handheld computers (PDA)
Handheld computers, also called personal digital assistants (PDAs), are battery-powered computers small enough to carry almost anywhere. Although not as powerful as desktops or laptops, handheld computers are useful for scheduling appointments, storing addresses and phone numbers, and playing games. Some have more advanced capabilities, such as making telephone calls or accessing the Internet. Instead of keyboards, handheld computers have touch screens that you use with your finger or a stylus (a pen-shaped pointing tool).