Classify Computer Size | Functionality

The following are the six varieties of computers. They are :

1. Desktop Computer 
2. Workstations
3. Notebook Computer
4. Tablet Computer 
5. Handled Computer
6. Smart Phones. 

Desktop Computer

A desktop computer is nothing but PC (Personal Computer) that is designed to sit on a desk or table. These are the systems that are being commonly used now in Schools, Homes, and Offices. This is not a machines do enable people to do their jobs with greater easy and efficiency, but they can be used to communicate, produce music, edit photographs and videos, play sophisticated games, and much more.

A desktop computer is full of size computer that is too big to be carried around the outside.

Workstations

A workstation is an specialized, single user computer that typically has more power and features than  a standard desktop PC. It is used for engineering applications (CAD/CAM),desktop publishing, scientists, engineers, animators, software development, and other such types of applications which require a moderate amount of computing power and relatively high quality graphics capabilities.

Workstations generally come with an large, high-resolution graphics screen, large amount of RAM, in-built network support, and a graphical user interface. Most workstations also have a mass storage device like disk drive, but a special type of workstation, called a disk less workstation, comes without a disk drive.

Notebook Computer

Note book computer is a type of computer approximately shape of these computer was 8.5 by 11 inch. The people set these devices on their lap, they are also called as laptop computers. These computers generally less than eight pounds. During use, the computers lid is raised to reveal a thin monitor and a key board. 

Notebook  are fully functional micro computers. The people who use them need the power of a full-size desktop computer whenever they go. Some notebook systems are designed to be plugged into a docking stations, which may include a large number monitor, a full size key board and mouse,or other devices.

Tablet Compute

A tablet computer is a commonly short to tablet, a mobile device, typically with a mobile operating system and LCD touchscreen display processing circuitry, and a rechargeable battery in a single thin, flat package.

Tablet PC's offer all the functionality of a notebook PC, but they are lighter and can accept input from a special pen called a stylus or a digital pen that is used to tap or write directly on the screen. Many tablets PC's also have a built-in micro phones and special software that accepts input from the user's voice.

Handled Computer

A popular type of handled computer is the Personal Digital Assistant (PDA). A PDA is is no larger than a small appointment book and is normally used for special applications such as taking notes, displaying telephone numbers and addresses, and keeping track of data's and agendas. 

Smart Phones

A Smart phones is a class of mobiles phones and mobile computer devices. It is distinguished from special feature phones by their stronger hardware capabilities and extensive mobile operating systems, which facility wider software, internet like web browsing over mobile broadband, and multimedia functionality like music, video, cameras and gaming etc.. 

These are large size cellular phones. Because these phones are offered advanced features not typically found in cellular phones, they are sometimes called smart phones. These features can include web and e-mail access.

It improves the hardware and faster wireless standards (such as LTE) have bolstered the growth of the smartphone industry. In the third quarter of 2012, one billion smartphones were in used worldwide. Globally smartphone sales was surpassed the sales figures for feature phones in early 2013.

Types Of Computer's

Type Of Computer's

A computer can be classified on several basics which is shown below:

A computer which is based on the basics of electronic or the operating system principle, They can be classified into :

a.Analog computer.

b.Digital computer.

c.Hybrid computer.

Analog Computer

Analog computer operates on input of continuously verifying electrical voltage. It measure the input rather than counting. These are powerful tools to solve differential equations.  They are mainly used in scientific design's and production environment's.

Digital Computer
All quantities are expressed as discrete digits or numbers and done with numerical digits. Mathematical expressions are represented as binary digits such as (0 and 1) and remaining all operations are done using these binary digits at a very high rate.

The digital computer basically knows addition. It converts other operations into addition then calculate. It is so much faster than the analog computer, computations are far more accurate.
Hybrid Computer
Hybrid computer combined the features of both analog and digital computers. In this computer some calculations are done in the analog portion of the computer and some done in the digital portion of it.

 

➤A computer which is based on the basics of personal of use, They can be classified into :

a. Special purpose computer.

b. General purpose computer.

Special Purpose Computer 

Special purpose computer is tailor made soley to cater to the requirements of a particular task or application.

Example:-Weather forecasting, power loom machine etc..

General purpose computer

The general purpose computer is basically designed to meet the needs of many different applications. The instructions was needed to perform a particular task are not wired permanently into the internal memory.

                                                      

Example:- Office work, way-bills, documents etc...

Definition & Features & Characteristics Of Computer.

Definition of Computer

A computer is an electronic device with the ability to accept the  input from user and its take process the data and get finally output of the results to the user. A computer will also have the ability store the users data for a long time.

Functions of a computer

If  any digital computer carries out five functions. They are:

1. It takes the data as a input.
2. It stores the data/instructions into memory and use it when required.
3. It processes the data and converts it into useful information.
4. It generates the output.
5. It controls all the above four steps.

Characteristics of Computer

The following are a list of characteristics that are mainly used to differentiate the computer.

They are :-

1. Accuracy
2. Storage 
3. Speed
4. Versatility
5. Diligence 
6. Reliability
7. Automation

Accuracy

Accuracy means to indicates the data processing in the computer which is taken from the user input. A computer is always processes the data with high accuracy. But some times while computing, due to human mistakes some inaccurate results may occur rarely.

Storage

A computer have contains the large storage of capacity.So the data can be storage in the memories. Memories are classified in to 2 types in the computers. The Below diagram shows about the types of memories.

They are 2 types of memories in the computer.
1.Primary Memory:- Primary memory is also known as volatile memory.It is again classified into 2 types they are :

• Ram
• Rom 

2.Secondary Memory:-  Secondary memory is also known as optional memory of a computer, which is used to store the data, files, movies, songs, videos, images etc.. The content of secondary memory is to store the data  permanently and whereas the content  of memory is non-volatile.

Example:- Hard disc, floppy disc, pen drive, compact disc.

Speed 

The rate at which computer process the instructions per second is called speed of the computer. Present the modern computers execute instructions within the Micro, Nano, and Pico seconds.

1 micro second = 1/10 (power of 6) per a second.

1 nano second   = 1/10 (power of 9) per a second.

1 pico second     = 1/10 (power of 12) per a second.

Versatility

A computer are used for variety of applications. They are not limited to any  particular job and even though they can function like a human being. Many software are available to perform different jobs with the help of computer. 

Diligence

In general way, There are some limitations to the human power.  
For Example:- Humans needs some rest after doing the certain work of time. 
But a computer is not like on that way, Because its a machine does not require such type of rest. It can process the same activity any number of times with same speed and accuracy. 

Reliability

1. A computer is a reliable machine.

2. Modern electronic  components have long lives.

3. Computer are designed to make maintenance easy.

Automation 

1. A computer is an automatic machine.

2. Automation means ability to perform the given task automatically.

3. Once a program is given to computer i.e stored in computer memory, the program and instructions can control the program execution without human interaction.  

Advantages 

• The uses of a computer for data processing in an organisation leads to reduction in papers work and results in speed up a process. 
• The data of electronic files can retrieve as when we required.
• It reduces the maintenance of cost problems. 

Limitations

• A computer is a machine that has no intelligence power to perform any task.
• Each instructions has to be given computer only that can be operated by  the human begin.
• It cannot take any decision on its own. It requires any instruction to operate.
• its functions as per a user's instruction only, So it is fully dependent on human skill.
• A computer have no feelings and emotions.
• It cannot make judgment based on feelings, taste, experience and knowledge unlike a human being.

Third Fourth Fifth Generation of Computer

Third Generation Computer (1965-1971):

The period of third generation was during in the year 1965 - 1971. The third generation of computer was developed the concept of integrated circuits called as IC's in transistors.

• A single IC has many transistors, resistors and capacitors and along with associative circuitry or chip of silicon. 
• The IC was invented by Jack kilby. IC's  are sometime called chips because of the way they are made.
• In this generation made computers smaller in size, reliable and efficient.
• The features of third generation was remote processing, time sharing, multi-programming operating system were used.
• In this generation computers offered more money and faster processing as well as development of first telecommunications stations on the earth could transmit and receive data from the satellites, enabling worldwide communications between computer systems. 
• High level languages like FORTRAN-ii TO IV, COBOL, PASCAL PL/1, BASIC, ALGA-68 were used this generations.

                               

The main features of third generations are:

1. IC's were used.
2. More reliable when in comparison to previous two generations.
3. Smaller in size.
4. Its produced a less heat.
5. More faster then previous generations.
6. Its so lesser maintenance.
7. Cost is very high.
8. Air conditioner is needed.
9. Its consumed lesser power.
10. Its supported high level languages.

Some computers of this generations were:

1.  IBM 360 series.

2. Honeywell-6000 series.

3. PDP (Personal Data Processor)

4. IBM-370/168.

5. TDC-316.

Fourth Generation Computer (1971-1980):

The period of fourth generation was during in the year 1971-1980. The technology of fourth generation computers was used VLSI (very large scale integrated circuit).

• A creation of tiny computers that designed on a chip gave way for the world's first micro-processor. It holds on a single chip in the entire control unit and arithmetic & Logical unit of a computer. The technique was called as VLSI.
• VLSI circuits having about 5000 transistors and other circuit elements and associated circuits on a single chip and made it possible as to have micro-computer of fourth generation.
• Fourth generation computers becomes more powerful, compact, reliable and  affordable. As a result, it gave rise to personal computer (PC) revolution is still going strong.
• The efforts to pack even more transistors on one chip have led to such developments as Intel's Pentium microprocessors. Although the high-level languages are still used extensively, All the high-level languages C, C++, DEBASE etc are appeared fourth generation.
• In this generation time sharing, real time, networks and distributed operating system were used.

                                               

The main features of Fourth generations are:

1. VLSI Advance technology used.

2. Its very cheap.

3. Its portable and reliable.

4. Use of PC's.

5. This is smaller in size.

6. Pipeline processing.

7. No need of AC.

8.A new concept of internet like LAN (local Area network), WAN (Wide Area Network) was introduced.

9. A Great developments in the fields of networks.

Some computers of this generations were:

1. DEC 10

2. STAR 1000

3. PDP 11

4. CRAY-1 (Super computer)

Fifth Generation Computer (1980-Till)

The period of fifth generation was during in the year 1980 - till date. In this fifth generation, the VLSI technology become ULSI (Ultra Large Scale Integrated) technology .

• It resulting in the production of micro processor chips having ten million electronic components.
• In this generation is based on parallel processing hardware AI (Artificial Intelligence) software.
• AI is an emerging branch in computer science, which interprets means and method of making computers think like human begins.
• All the high-level languages like C and C++, Java, .Net etc. are used in this generation.

                                     

Artificial Intelligence includes:

1.Robotics

2.Neural networks

3.Game Playing

4.Development of expert systems to make decisions in real life situations.

5.Natural language understanding and generation.

The main features of fifth generation are:

1. VLSI technology

2. Development of true artificial intelligence

3. Development of Natural language processing

4. Advancement in Parallel Processing

5. Advancement in Superconductor technology

6. More user friendly interfaces with multimedia features

7. Availability of very powerful and compact computers at cheaper rates

Some computer types of this generation are:

1. Desktop                      4. Ultra Book

2. Laptop                        5. Chrome Book

3. Notebook

First Second Generations Of - Computer's

Generations of a computer

Generation of a computer terminology is totally changed its depends on computer technology  was being used. Initially, the term generation  was used to distinguish between the hardware  and software technology. 

But now a days, generations includes the hardware and software which is together make up an entire computer system. They are totally five computer generations now till date. So each generation has been discussed in detail along with their time period also.

➤The First Generation: The period of first generation was during 1946-1959, Vacuum tube based.
➤The Second Generation: The period of second generation was during  1959- 1965, Transistor based.
➤The Third Generation: The period of third generation was during 1965-1971, Integrated circuit based.
➤The Fourth Generation: The period of fourth generation was during 1971-1980, VLSI microprocessor based.
➤The Fifth Generation: The period of fifth generation 1980-on wards, ULSI microprocessor based. 

➤ First Generation Computers (1946-1959)

The period of first generation computer was during in the 1946 to 1959. The first generation of computer used vacuum tubes as the basics components for memory and circuitry for CPU (Central Processing Unit). 

• The components which was used in first generation such as tubes, electronic bulbs that produced a lot of heat and were prone to frequent fusing of the installations.
• They were very expensive, large and slow which was offered only large organisations.
• In this generation only batch processing operating  system were used as well as punched cards, paper tape, and magnetic tapes were used as a input devices. 
• These computers were given instructions in machine language, which is composed entirely of the number 0 and 1. It is very difficult to work and hard to interpret. 
• The vacuum tubes failed frequently, so the first generation of computers were down and not working much of the time. 

                                              

Main features of first generations are:

1. Vacuum tube technology
2. Unreliable
3. Supported machine language only
4. Very costly
5. Generated lot of heat
6. Slow process
7. Huge in size
8. Need a air conditioner.
9. Non portable.
10. Consumed a lot of electricity. 

Some of the computer this generation were:

1. ENIAC 
2. EDVAC
3. UNIVAC
4. IBM-701
5.IBM-650.

➤ Second Generation Computers (1959-1965)

The period of Second generation Computer was during in the year 1959-1965. This time break through in the computer world occurred in the second generation computers were large, unreliable vacuum tubes were replaced by transistors.

• Second generation computer were used that were cheaper, consumed less power, more compact in size, more reliable and faster than first generation computers.
• Transistors are small, require very little power and run efficiently.
• In this generation, Memory used on magnetic cores were used as primary memory and magnetic tape and magnetic disks as secondary devices.
• In this generation assembly language and high-level programming languages like FORTRAN, COBOL were used. This computers used batch processing and multiprocessing operating system.
• This generation computer had some problems. The input and output devices were so slow. 
• Communication was fairly slow, but a new method of exchanging data and ideas was available.

The main features of second generation are:

• Uses of transistors.
• Reliable in comparison to first generation computers.
• Smaller size as compared to first generation computers
• Generated less heat as compared to first generation computers.
• Consumed less electricity as compared to first generation computers.
• Faster than first generation computers.
• Still very costly.
• A.C. needed.
• Supported machine and assembly languages.

Some computers of this generation were:

1. IBM 1620
2. IBM 7094

3. CDC 160
4. CDC 3600

5. UNIVAC 1108