Computer - C
sed for T
echnical and E
A Computer is an electronic machine that can solve different problems, process data, store & retrieve data and perform calculations faster and efficiently than humans
is called the "Grand Father" of the computer. The First mechanical computer designed by Charles Babbage was called Analytical Engine
. It uses read-only memory in the form of punch cards.
Characters of Computer
- High Speed-:
- Data Storage Capacity-:
Flexibility means that a computer can work in many areas like you can use your computer system to:
- Watch movies or videos
- Listen sounds or music's
- Play games
- See pictures
- Write textual documents and save
- Open and read anything
- and many more
Advantages of Computer
- Increase your productivity -
- Connects you to the Internet -
- Can store vast amounts of information and reduce waste-
- Helps sort, organize, and search through information-
- Get a better understanding of data-
- Keeps you connected -
- Can help you learn and keep you informed -
- Can make you money -
- Improves your abilities-
- Save time -
Limitation of Computer
- Depend on users input.
- Computer have no imagination.
- Cannot detect error in logic.
- Only expert user can work on it.
- Cannot take its own decisions.
- No Self-Intelligence
- No Thinking and Decision Making Power
- No Feeling
- No learning power
Types of Computers
There are different types of Computers with respect to size, speed, storage capacity and cost, computer can be classified in the following types-
- Micro Computer
- Mini Computer
- Mainframe Computer
- Super Computer
1. Micro Computer-
These computers are small in size and cost less.
They are usually designed for personal use therefore they are also called personal computer.
They are mainly used in homes, schools, offices, shops, banks, etc. Examples are: Commodore 64, IBM PC. These computers are given different names according to their usage.
Types of Micro Computers
- These computers can easily be accommodated on the top of a desk due to their small size. Hence they are also called desktop computer.
- These computers are small in size and can be placed on the lap. These are battery operated computers and can be carried in briefcase and used anywhere while travelling.
- These are the smallest computer, also called PDAs (Personal digital assistant). They lack the power of a desktop or laptop computers, but offer features for users who need limited functions and small size.
2. Mini Computer-
These computers are bigger in size than that of Micro Computers.
They have a higher processing speed and are costlier than Micro Computers.
Several users can use it at the same time.
They are used in banks, universities and in big organizations. Example, PDP-8
3. Mainframe Computer-
These computers are very powerful.
They are big in size with a large memory and high speed.
They are designed to tackle huge amount of data.
More than hundred users can use a mainframe computer simultaneously. They are used in networked environment.
Mainframe computer are very expensive and can be used in large business organizations, universities, banks scientific laboratories, airline/ railway ticket reservation, state exchange markets etc.
4. Super Computer-
They are the most powerful computers with a huge processing speed.
These computers are used for weather forecasting space research, satellite control etc. Examples are CRAY-1, CRAY2, PARAM, ETA, A-10 etc.
was the first calculation device.
Charles Babbage is considered to be the father of computes. He invented difference engine in 1822 and analytical engine in 1833.
Augusta Ada was the first programmer.
(Electronic Numerical Integrator and Computer) was the first general purpose electronic digital computer.
(Universal Automatic Computer) was the first computer to handle both numeric and text data.
Computers are categorized into four types with respect to speed, storage capacity, size and cost.
Application of Computer
Application of computers in various fields.
1. Business -
A computer has high speed of calculation, diligence, accuracy, reliability, or versatility which has made it an integrated part in all business organizations. Computer is used in business organizations for −
- Payroll calculations
- Sales analysis
- Financial forecasting
- Managing employee database
- Maintenance of stocks, etc.
2. Banking -
Today, banking is almost totally dependent on computers. Banks provide the following facilities −
Online accounting facility, which includes checking current balance, making deposits and overdrafts, checking interest charges, shares, and trustee records.
- ATM machines which are completely automated are making it even easier for customers to deal with banks.
3. Insurance -
Insurance companies are keeping all records up-to-date with the help of computers. Insurance companies, finance houses, and stock broking firms are widely using computers for their concerns. Insurance companies are maintaining a database of all clients with information showing −
- Procedure to continue with policies
- Starting date of the policies
- Next due installment of a policy
- Maturity date
- Interests due
- Survival benefits
4. Education -
The computer helps in providing a lot of facilities in the education system.
- The computer provides a tool in the education system known as CBE (Computer Based Education).
- CBE involves control, delivery, and evaluation of learning.
- Computer education is rapidly increasing the graph of number of computer students.
- There are a number of methods in which educational institutions can use a computer to educate the students.
- It is used to prepare a database about performance of a student and analysis is carried out on this basis.
5. Marketing -
In marketing, uses of the computer are following −
Advertising − With computers, advertising professionals create art and graphics, write and revise copy, and print and disseminate ads with the goal of selling more products.
- Home Shopping − Home shopping has been made possible through the use of computerized catalogues that provide access to product information and permit direct entry of orders to be filled by the customers.
Computers have become an important part in hospitals, labs, and dispensaries. They are being used in hospitals to keep the record of patients and medicines. It is also used in scanning and diagnosing different diseases. ECG, EEG, ultrasounds and CT scans, etc. are also done by computerized machines.
Following are some major fields of health care in which computers are used.
- Diagnostic System − Computers are used to collect data and identify the cause of illness.
- Lab-diagnostic System − All tests can be done and the reports are prepared by computer.
- Patient Monitoring System − These are used to check the patient's signs for abnormality such as in Cardiac Arrest, ECG, etc.
- Pharma Information System − Computer is used to check drug labels, expiry dates, harmful side effects, etc.
- Surgery − Nowadays, computers are also used in performing surgery.
7. Engineering Design-
Computers are widely used for Engineering purpose.
One of the major areas is CAD (Computer Aided Design) that provides creation and modification of images. Some of the fields are −
- Structural Engineering − Requires stress and strain analysis for design of ships, buildings, budgets, airplanes, etc.
- Industrial Engineering − Computers deal with design, implementation, and improvement of integrated systems of people, materials, and equipment.
- Architectural Engineering − Computers help in planning towns, designing buildings, determining a range of buildings on a site using both 2D and 3D drawings.
8. Military -
Computers are largely used in defence. Modern tanks, missiles, weapons, etc. Military also employs computerized control systems. Some military areas where a computer has been used are −
- Missile Control
- Military Communication
- Military Operation and Planning
- Smart Weapons
9. Communication -
Communication is a way to convey a message, an idea, a picture, or speech that is received and understood clearly and correctly by the person for whom it is meant. Some main areas in this category are −
10. Government -
Computers play an important role in government services. Some major fields in this category are −
- Sales tax department
- Income tax department
- Computation of male/female ratio
- Computerization of voters lists
- Computerization of PAN card
- Weather forecasting
Classification of Computer Parts
All physical parts of computer that we can touch or feel is called "HARDWARE".
Types of Hardware device
- Input Device In which device we feed data into the Computer is called Input Device. Most commonly input device are Mouse & Keyboard.
In which device we get the result is called Output Device
Software is a set of Program that we can’t touch
Software is a set of instructions, data or programs used to operate computers and execute specific tasks
Types of Software
1. System Software (Operating System)
- System Software (Operating System)
- Application Software
Operating system is needed to operate a computer. An operating system controls the overall activities of a computer. It acts as a link between the user and the hardware and enables them to work together.
An Operating System (OS) is an interface between a computer user and computer hardware. An operating system is a software which performs all the basic tasks like file management, memory management, process management, handling input and output, and controlling peripheral devices such as disk drives and printers
important functions of an operating System.
|Sr No.||OS Name||Company Name|
|1 ||Windows ||Microsoft |
|1 ||MAC ||Apple |
|1 ||iOS ||Apple |
|1 ||Android ||Google |
|1 ||Symboin ||Nokia |
2. Application Software
- Memory Management
- Processor Management
- Device Management
- File Management
- Other Important Activities
- Security −
- Control over system performance −
- Job accounting −
- Error detecting aids −
- Coordination between other softwares and users −
Application software is a program or group of programs designed for end users. These programs are divided into two classes: system software and application software. While system software consists of low-level programs that interact with computers at a basic level, application software resides above system software and includes applications such as database programs, word processors and spreadsheets. Application software may be bundled with system software or published alone.
Application software may simply be referred to as an application.
- MS Office
- Google Chrome
- UC Browser
A memory is just like a human brain. It is used to store data and instructions. Computer memory is the storage space in the computer, where data is to be processed and instructions required for processing are stored.
types of Memory
- Primary Memory
- Secondary Memory
(Randam Access Memory)
RAM (Random Access Memory) is the internal memory of the CPU for storing data, program, and program result. It is a read/write memory which stores data until the machine is working. As soon as the machine is switched off, data is erased.
(Read Only Memory)
ROM stores some permanent set of instruction for a computer. As soon as we switch on the computer, it follows the set of instructions located in the ROM. These instructions are executed automatically. The computer then gets ready for us to work on. The instructions inside ROM are written by the manufacturer of the computer and are not changeable, hence the name READ-ONLY. These instructions are not lost when the computer is switched off.
Difference between RAM and ROM-
|| Read and write both are allowed.
|| Only read is allowed.
|| All the instructions and data are stored inside this area before being processed.
|| Contains the instructions that are required by the computer to start.
|| This is a temporary storage area.
|| This is a permanent storage area.
|| It gets cleared as soon as the computer is switched off.
|| The instructions are not changed even when the computer is switched off.
Primary memory has limited storage capacity and is volatile. Secondary memory overcome this limitation by providing permanent storage of data and in bulk quantity. Secondary memory is also termed as external memory and refers to the various storage media on which a computer can store data and programs. The Secondary storage media can be fixed or removable
- Pen Drive
- CD (Compact Disc)
- Hard Disk
- DVD (Digital Versatile Disc)
Memory Measring Units
| 8 BITS || = 1 BYTE |
| 1024 BYTES || = 1 KB (KILOBYTE) |
| 1024 KB (KILOBYTE) || = 1 MB (MEGABYTE) |
| 1024 MB (MEGABYTE) || = 1 GB (GIGABYTE) |
| 1024 GB (GIGABYTE) || = 1 TB(TERABYTE)|
Soft Copy & Hard Copy
A soft copy an electronic copy of some type of data, such as a file viewed on a computer's display or transmitted as an e-mail attachment. Such material, when printed, is referred to as a hard copy .
- First GenerationThe period of first generation: 1946-1959, Vacuum Tube based
- Second Generation
The period of Second generation: 1959-1965, Transistor based
- Third Generation
The period of third generation: 1965-1971, Integrated circuit based
- Fourth Generation
The period of Fourth generation: 1971-1980 microprocessor based
- Fifth Generation
The period of Fifth generation: 1980-onwords artificial intelligence based
We have made many folders to keep our papers that are of similar kind in one folder, e.g., the letters that we have received from my friends are in one folder and the circulars from my school are in a separate folder. Likewise papers of one subject are in one folder and paper of another subject are in another folder.
When we write or draw something, we save it so that we can use it later. We give name to the document so that we can locate it later, when we required. This document called a file in computers.
Therefore, files are used to store or save data and information. Each files given a name. just as our name gives us our identity, the name of a file becomes in identity.
Recycle bin is similar to a dustbin. All the files which are deleted are put inside recycle bin. We can get back the files from the recycle bin folder. But once the recycle bin is emptied and cleared of file, cannot be recovered.
To empty the recycle bin, right click on the recycle bin icon and then left click on empty recycle bin option. To bring back a file, right click over the file which is in recycle bin and then left click on restore. The file will be placed back to its original location.