What is software? Explain different types of software?

Semester :-1

Unit:-1

What is software? Explain different types of software?
Ans:-
        The computer is a machine and it can not think and do its own. Since it has no intelligent quotient, it must be instructed to carry out any task. Hence it is required to specify the set of sequential instructions that the computer can perform to solve any task.
Software is basically "the set of instructions grouped into programs that make the computer to function in the desired way. It is a collection of programs to perform a particular task.

System software :

A system software is a collection of programs designed to operate, control and extend processing capabilities of computer and which makes the operation of a Computer system more effective and efficient. The system software can be devised into two types 

1. Operating systems 
2. Language Translators/processor

Operating system :

An operating system plays an important role in a computer system which controls all other components of the computer system. If there is no operating system then there is no computer. It controls the CPU Memory, input / output Devices etc... It is responsible for smooth functioning and efficient operating of the computer system. Some of the popular operating systems are DOS, WINDOWS, UNIX and LINUX etc.... 

Language Translator / processors:

A programmer can write program In high level language because it is much easy to understand by the computer and convert into is own machine language (machine language  the language processors are assembler, interpreter, compiler. 

Application software :

Application software is a set of programs necessary to carryout operations for a specific application  These are the programs written by programmers to enable computer to perform a specific task. Applications software can be divided into two categories.

1. Special purpose application software 
2. General purpose application software 

Special purpose application software :

This is based upon the customer requirements. This is developed to meet all the requirements mentioned by the customer. This requirement cannot be directly installed on any other user's workplace, because requirement may differ from one customer to another customer so this software may not fulfil to everyone. 

General purpose application software :

This type of software developed for general requirements for carrying out a specific task. Here many customers can use simultaneously due to fulfillment of all customers. 

What is the Deference of Hardware and software

Semester :-1

Unit:-1

What is the Deference of Hardware and software.
Ans:-

Discuss about Essential Computer Hardware - processing Devices - Memory Devices - input/output Devices.

Semester :-1

Unit:-1

Discuss about Essential Computer Hardware - processing Devices - Memory Devices - input/output Devices.
Ans: 
        Any type of computer system contains four types of hardware, they are

• Processor 
• Memory 
• Input and output 
• Storage

1. Processor : the processor is like the brain of the computer, it organizes and carries out instructions that come from either the user or the software. In a personal computer the processor usually consists of one or more specialized chips, called microprocessors, which are silvers of silicon or other material etch with many tiny electronic circuits. To process data or complete an instruction from a user or a program  the computer passes electricity through the circuits.
2. Memory : Memory is an internal storage area in the computer, which is used to store data and programs either temporarily or permanently. Computer memory can be broadly divided into two groups - primary memory and secondary memory.
3. Input and output : input devices accept data and instructions from the user or from another computer system. Output devices return processed data to the user or to another computer system. The input devices work with personal computers are :

1. The keyboard is the most common input device which is used accepts letters, numbers, and commands from the user. 
2. The mouse, which is used to selection options on the computer screen 
3. The trackball and TouchPad are variations of the mouse and enable you to draw or point on the screen 
4. The joystick is a rotating lever mounted on a motionless best that is well suited for playing video games
5. A scanner can copy a printed page of text or a graphic into the computer's memory 
6. A digital camera can record still images, which you can view and edit on the computer 
7. A microphone enables you to input your voice or music as data into computer 
8. The most common output devices are the monitor and the printer 
9. The speakers or headphone are another kind of output Device which produce sound 
10. A touch screen is an i/o device I. E it acts are input and output device
11. Communication devices are the most common type of device that can perform both input and output Examples : Modems, Network Interface Cards (NICs). 

4. Storage : The Computer primary memories are volatile/temporary. That's way a Computer also needs a place to keep program files and related data permanently when they are not in use, ever when the computer is turned off. There are two main types of computer storage : magnetic and optical.

1. Data storage is a critical component of any computer system. Magnetic storage is one of the most affordable ways to store large amounts of data and has been implemented using magnetic tape, floppy disks and hard disk drives
2. Optical storage devices are any storage methods that use a laser to store and retrieve data from optical media.  Optical storage media includes CD-ROM, DVD-ROM, DVD-RAM, WORM cartridges, erasable optical cartridges and removable mass storage media, which includes flash drives and removable disk, or RDX. 

Discuss about the parts of a Computer system Hardware, Software, Data and Users.

Semester :-1

Unit:-1

Discuss about the parts of a Computer system Hardware, Software, Data and Users.
Ans:- 
         Computer come in many varieties, from the tiny computers to the supercomputers. But no matter how big it is or how it is used every computer is part of a system. A Complete computer system consists of four parts :

• Hardware 
• Software 
• Data 
• User

Hardware : the mechanical devices that make up the computer are called hardware. Hardware is any part of the computer you can touch. A computer hardware consists of interconnected electronic devices that you can use to control the computer operation input and output.
Software : software is a set of instructions that makes the computer perform tasks. In other words software tell the computer what to do. Some programs exist primarily for the computer use to help it perform tasks and manage its own resources. 
DATA : Data consist of individual facts or pieces of information that by themselves may not make much sense to a person. A Computer's primary job is to process these tiny pieces of data in various ways, converting them into useful information.
Users : A user is a person who uses a computer or network service. Users generally use a system or a software product without the technical expertise required to fully understand it. Power users use advanced features of programs, through they are not necessary capable of computer programming and system administration. A user often has a "user account" and is identified to the system by a "username" 

COMPUTER APPLICATIONS

COMPUTER APPLICATIONS

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Discuss about Computers for Individual Users.

Semester :-1

Unit:-1

Discuss about Computers for Individual Users.

Ans:-

          Most Computers are meant to be used by only one person at a time. Such Computers are often shared by several people. But only one user can work with the machine at any given moment. The five primary type of Computers in this category are 

Computers for Individual Users

• Desktop computers
• Workstations
• Laptops
• Network Computers
• Hand held Devices

Desktop computers:-

                                      A desktop computers is the most popular model of PCs. The system unit of the desktop PC can be placed flat on a desk or table. It is widely used in homes and offices.

Workstations:-

                           A workstation is a specialized, single user computer that typically has more powerful than a standard desktop PC. These machines are popular among scientist, engineering's and animators who need a system with greater than average speed and the power to perform sophisticated tasks. Workstations often have large, high resolution monitors and accelerated graphics handling capabilities, making them suitable for advanced architectural or engineering design, modeling, animation and video editing.

Laptops:-

                 Laptops are very handy and can easily carried from one place to another. They m hiay also be placed on the user's lap. Hence, laptops are very useful, especially when going on long journeys.

Laptops operate on a special battery and do not always have to be plugged in like desktop computers. The memory and storage capacity of a laptop is almost equivalent to that of a desktop computers. As with desktop computers, laptops also have a screen, keyboard and a trackpad or trackball, which serves as the mouse. These computer are very popular among business travelers.

Network Computers:-

                                       A Computers With minimal Memory, disk storage and processor power designed to connect to a network, especially the Internet. The idea behind network Computers is that many users who are connected to a network don't need all the computer power they get from a typical personal computer. Instead they can rely on the power of the network servers.

Hand Held Computer:-

                                         Handheld personal Computers are computing devices small enough to fit in your hand. Some examples of handheld computers are:

• Personal Digital Assistant (PDA)
• Cellular phones
• H/PC pro Device.

A popular type of handheld computer is the personal Digital Assistant PDA, A PDA is no longer then a small appointment book and is normally used for special applications, such as taking notes, displaying telephones numbers and addresses, and keeping track of dates or agendas.

Cellular phones are web enabled telephones that have features of both analogue and digital devices. Such phones are also known as smart phones. Because, in addition to basic phone capabilities, they also support access the internet and send emails and faxes.

H/PC pro Devices is the new development in handheld technology. The size and features of the H/PC pro Device is more than PDAs but less than that of typical notbook PCs. The H/PC pro Device includes a full sized keyboard, RAM with very low storage capacity, and a slow speed processor these Devices do not have a secondary storage disk.

Discuss about Computers for Individual Users

Semester:-1

Unit:-1

Discuss about Computers for Individual Users. ?
Ans:-
          Most Computers are meant to be used by only one person at a time. Such computers are often shared by several people. But only one user can work with the machine at any given moment. The five primary type of computers in this category are
Computer for Individual Users

• Desktop computers
• Workstation
• Laptops
• Network computers
• Hand held devices

Desktop PCs:
                       A desktop PC is the most popular model of PCs. The system unit of the desktop PC can be placed flat on a desk or table. It is widely used in homes and offices.

Work stations:
                         A workstation is a specialized , single user computer that typically has more powerful than a standard desktop PC. These machines are popular among scientist , engineers, and animators who need a system with greater than average speed and the power to perform sophisticated tasks. Workstations often have large, high resolution monitors and accelerated graphics handling capabilities, making them suitable for advanced architectural or engineering design, modeling, animation and video editing.
Laptops:
               Laptops are very handy and can easily carried from one place to another. They may also be placed on the user's lap . Hance , laptops are very useful, especially when going on long journeys.

Laptops operate on a special battery and do not always have to be plugged in linke desktop computers. The memory and storage capacity of a laptop is almost equivalent to that of a desktop computer. As with desktop computers, laptops also have a screen, keyboard, and a trackpad or trackball , which servers as the mouse. However   a drawback is that laptops are generally more expensive than desktop computers. These computers are very popular among business travelers.

Network Computers:

                                      A Computer with minimal Memory, disk storage and processer power disigned to connect to a network, especially the Internet. The idea behind network Computers is that many user who are connected to a network don't need all the computer power they get from a typical personal computer. Instead , they can rely on the power of the network servers.

Hand Held Computer:

                 Handheld personal Computers are computing devices small enough to fit in your hand . Some examples of handheld computers are:

• Personal Digital Assistant (PDA)
• Cellular phones
• H/PC pro Device.

               A popular type of handheld computers is the personal Digital assistant(PDA). A PDA is no larger then a small appointment book and is normally used for special applications, such as taking notes, displaying telephone numbers and addresses, and keeping track of dates or agendas.

                Cellular phone are web enabled telephones that have features of both analogue and digital devices. Such phones are also known as smart phones. Because, in addition to basic phone capabilities, they also support access the internet and send e mails and faxes.

                H/PC pro Devices is the new developments in handheld technology. The size and features of the H/PC pro Devices is more than PDAs but less than that of typical notbook PCs. The H/PC pro Devices includes a full sized keyboard, RAM with very low storage capacity, and a slow speed processor. These Devices fo not have a secondary storage disk.

Explain different Computer Hardware parts

Semester:-1

Unit:-5

Explain different Computer Hardware parts. ?
Ans:-
          The physical parts of the computer that we can see and touch are known as computer hardware. Computer software is just like the human soul, which can not be touched and computer hardware is like body which we can see and touch.
Motherboard : 

• This is the part of the computer where everything is placed or connected to. It holds the slot and ports where the other parts will be attached.
• When upgrading or buying a motherboard make sure it contain the most recent slots and ports to ensure that you will not limited in the kind of parts you install into it.
• Example there are two kinds of ports for a CD/DVD drive and hard drive. It can be the earlier IDE or a SATA port. Some motherboards can carry both IDE and SATA during the period where SATA is still new.

Processor :

• This is the "brain" of the computer because it does necessary computations and logical operations to run a program.
• At the moment of writing the most known processors brands are Intel and AMD . Intel are best for office and desktop publishing work while AMD is best for gaming.

RAM :

•            This means Random Access Memory and is responsible for becoming temporary storage for use by actively running programs and processes of a computer.
• Generally the higher the RAM the more programs you can run at the same time but the processor would play a big part two in determining if these programs will run smoothly.
• RAM comes in size of 512 kb , 1GB, 2GB, 4GB and 8GB. Usually there are only two slots available so if you hear that they are selling a computer with 3GB of RAM then it is most likely composed on a 2GB and 1GB sticks of RAM.
• Typically a laptop RAM would come also in smaller size.

Hard Disk Drive :

• The programs, files and pictures are stored in a hard disk drive.
• It comes in either with a SATA port or IDE port, the latter being the older model.
• SATA allows much higher capacity of data that can be transferred with also a much slimmer cables to be used.
• Desktop hard disk drives are about 3.5 inches while laptop hard disk drives are 2.5 inches.
• It comes in storage sizes of 80GB, 120GB, 160GB, 240GB, 320GB, 640GB, 1TB, 2TB, 3TB etc .
• Please note that if you get a 649GB it doesn't equally mean to be 640GB exactly. It may fall off a few kilobytes because the conversion is not exact. 1024 bytes = 1 kilobytes(KB), 1024 KB = 1 Megabytes (MB), 1024 MB = 1 Terabytes (TB), 1024 TB = 1 Gigabytes(GB).

CD / DVD Drive :

• This is where you put your CDs and DVDs do you can view their content inside the computer.
• If you get one with a write feature it can also be used to back-up or save data from your computer into a CD and DVD. The CD and DVD you must though must also be writable.
• Like the hard disk drive it can also be either for a SATA or IDE port , the latter being the older model.
• A desktop can carry as many as 3 CD-DVD drives at the same time depending on the number of bays which can be carried by the case used however for a laptop there is only one CD-DVD drive available, sometimes none at all like with netbooks.

Internal CD/DVD drive

External CD/DVD drive

Video Card :

• They are expansion cards which allows to creates the images to be displayed out to the monitor.
• Motherboards nowadays have their on-board video and this would share memory from the RAM but some more advanced boards would have their dedicated Memory even if it is on-board specially with laptops. 
• You may consider using a video Card instead of an on-board video if you wish to run more power hungry graphics like for computer games and multimedia editing.
• Be careful not just to buy any kind of video Card and always check what your motherboard can handle are there now several lost types for use on video cards. The latest now are PCIs.

Explain in detail Magnetic Disks

Semester:-1

Unit:-4

Explain in detail Magnetic Disks
Ans:-
          A round plate on which data can be encoded. There are two basic types of disks: magnetic disks and optical disks.
            On magnetic disks, data is encoded as microscopic magnetized needles on the disk's surface. You can record and erase data on a magnetic disks any number of times, just as you can with a cassette tape. Magnetic disks come in a number of different froms:
Floppy Disk :
                       A typical 5 1/4 - inch Floppy disk can hold 360K or 1.2MB (megabytes). 3 1/2 - inch floppies normally store 720K, 1.2MB or 1.44MB of data.

Hard disk : 
                    Hard disks can store anywhere from 20MB to more than 200 GB. Hard disks are also from 10 to 100 times faster than Floppy disks.
Removable Cartridge :
                                        Removable Cartridge are hard disks encased in a metal or plastic Cartridge, so you can remove them just like a Floppy disks. Removable Cartridge are very fast , though usually not as fast as fixed hard disks.

Discuss about Various Secondary Storages Devices.

Semester:-1

Unit:-4

Discuss about Various Secondary Storages Devices ?

Ans:-
          When the computer is switched off, anything stored in the RAM is lost. To avoid this situation, magnetic disks are used to store data permanently. The data , on these disks, won't be affected when we turn off our computer.
a) Floppy Disk : 
                            A Floppy Disk is a reusable data storage device that is composed of a disk of thin, flexible ("Floppy" ) magnetic storage medium encased in a square or rectangular plastic shell. Also called a " diskette", the Floppy is a flexible circle of magnetic material similar to magnetic tape , except that both sides are used. The read/write head contact the surface through an opening in the plastic shell or envelope. Floppies rotate at 300 RPM, which is from 10 to 30 times slower than a hard disk. Floppy disks basically come in three sizes, they are 8 inches, 5 1/4 inch , and 3 1/2 inch .

b) Hard Disk :
                        A hard disk, is also a permanent storage , where we can store lot of information. Capacity of a hard disk is measured in megabytes ( MB), Gigabytes (GB) or Terabytes (TB) and they come in various different sizes. Usually every computer now a day comes with hard disk.

The information in hard disk is stored in circular magnetic disks called plates , in the form of program files and data files.
c) CD-ROM ( Compact disk-Read only memory) :
                  CD-ROM is also one of the commonly used secondary storage device. The main advantage of CD-ROM is, they can store large volumes of data I.e., 700 MB to 1.4 GB and also they are cheaper and easy to handle. It is made up small plastic disk, coated with aluminum or silver for magnetization. A layer or transparent plastic is further deposited on the disk . The data is recorded in spiral tracks and the data once recorded cannot be deleted or rewritten , but can be read any number of times .
               In this technology, a high power laser beam is used to record data by burning tiny pits in the surface of the hard plastic disk . To read the data, a low power laser beam is used to scan the disk surface. The data are stored in binary digits . When the laser beam reflect from the smooth surface of the disk it is interpreted as a 1 bit and when the beam enters the tiny pits it is interpreted as a 0 bit .
Advantages : 

• High Storage Capacity
• Easy to use in multimedia applications.
• Handled easily
• Can read / Rewrite using CD-RW's

Disadvantage: 

• CD Writing can be done carefully
• Should be kept free from dust and heat.

d) Magnetic Tape :
                                 Magnetic Tape is the oldest form of secondary storage device. It is one of the popular storage medium for storing large amount of sequential data . It is also used as a backup storage for data stored on on-line storage devices.
The magnetic tape medium is a plastic ribbon usually 1/2 inch or 1/4 inch wide and 50 to 2400 feet long. It is coated with a magnetizable recording material such as iron-oxide or chromium dioxide . Data are recorded on the tape in the form of tiny invisible magnetized and non-magnetize spots on the coated surface of the tape.
Advantages :

• Non-volatile Memory
• Voluminous data can be stored.

Disadvantages :

• Only sequential data processing
• Complex mechanism required.
• After few days the data can be mounted to tape , we need to recall the data to store it into hard disk as and when required .

Fig: Magnetic Tape

Elucidate Data processing in computer.

Semester:-1

Unit:-3

Elucidate Data processing in computer.?

Ans:-

          Before data is processed by a computer. It has to be fed into the computer using a keyboard. Mouse or another input device. The central processing unit ( CPU) analyzes the raw data and processes it into sensible information. The CPU receives instructions from the user and issues prompts accordingly. After the data is processed. It is translated to output formats that are easily understandable by the user.

       The processed data is displayed on the computer for editing, viewing or playing. The computers CPU then receives instructions from the user to save the data securely on the hard drive . Later, the user can choose to modify, copy, move , edit or delete the data. Some of the output values that data is converted into are documents , video files and audio files.

            A computer system is comprised of three main parts : hardware, software and users. All components connected to the computer via cable or wireless access point are hardware. These are primarily the tangible parts that include the CPU , monitor keyboard and mouse. In addition, machines such as printers and scanners are considered part of the computers hardware. Software consists of the computer applications installed in the computer and used to execute functions. Users are the people who provide instructions to the computer.

Explain in detail Data Representation in Computers.

Semester:-1

Unit:-3

Explain in detail Data Representation in Computers. ?

Ans:-
           All data is represented by the state of the computer's electric switches. A switch has only two possible states 'ON'and ' OFF' so it can represent only two numeric values ( IE 0 and 1). To a computer ,when a switch is 'OFF', it represents a 0; when a switch is 'ON', it represents a  1. Because computers worked based on the binary number system. This number system base is 2. It contains digits 0 and 1. The binary digit either 0 or 1 is called BIT. 
Tax codes:-
                      Early programmers realized that they needed a  standard text code that was agreeable to all of them . In such a system,  numbers would represent the  letter of the alphabet, punctuation marks,  and other symbols. This standard code system would enable any programmer to use the same combinations of numbers to represent the same individual pieces of data.  The four most popular text code systems invented are the following :
EBCDIC:- 
                   EBCDIC stands for Extended Binary coded Decimal Interchange code. EBCDIC is an eighth bit code that defineds 256 symbols. It is still used in IBM mainframe and mid-range systems , but it is rarely encountered in personal computers .
ASCII:-
              ASCII stands for the American standard code for information interchange. The ASCII character set is most commonly used in all types computers.  ASCII is an eighth-bit code that specifics characters from values from 0 to 127. 
Extended ASCII:-
                                 Extended ASCII  is an eighth bit code that specifics the characters for values from  128 to 255. The first 40 symbols represent special punctuation.  The remaining symbols are graphic symbols. 
Unicode :-
                    The Unicode Worldwide Character standard  provides up to  four bytes to represent each letter , number or symbol. With four  bytes , enough Unicode codes can be created to represent more than 4 billion different characters or symbols.  This total is enough for every unique character and symbol in the world . One major advantage that Unicode has over other text code systems is it's compatibility with ASCII  codes.  The first 256 codes in Unicode are identical to the 256 codes used by the ASCII and Extended ASCII systems. 

Discuss about the keyboard.

Semester :-1

Unit:-2

Discuss about the keyboard.?
Ans:-   

           An input device Is used to feed data and instructions into the computer. The keyboard is the main input device for computers.
               Using a keyboard, the user can type a document,use keystroke shortcut,access menus,play games and perform numerous other tasks.most keyboards have between 80 and 110 keys, which include the following: 
Typing keys :-
                          These include the letters of the alphabet.The layout of a keyboard is known as QWERTY for its first six letters. The QWERTY pattern has been a standard right from the time computer keyboards were introduced.
Numeric keys:-
                             These include a set of 17 keys, arranged in the same configuration found on calculators to speed up data entry of numbers.when the num lock key is set to on, the user can type number dot or input the symbols/,*,-, and+. When the num lock key is set to off , the numeric keys can be used to move the cursor on the screen.
Function keys :-
                               These are used by applications and operating systems to input specific commands.they are often placed on the top of the keyboard in a single row . function key can be programmed so that their functionality varies from one program to another.
Control keys:-
                           These are used to handle control of the cursor and the screen. Four arrow keys are arranged in an inverted T-type fashion between the typing and the numeric keys, and are used to move the cursor on the screen in small increments. In addition to the arrow keys, there are other cursor keys ( or navigational keys ), such as :

• Home and End to move the cursor to the beginning and end of the current line , respectively
• Page up and page down to move to the previous and the next pages , respectively
• Insert to enter a character between two existing characters
• Delete to deleted a character at the cursor position

Other common control keys on the keyboard include control ( Ctrl) , Alternate ( Alt), Escape( ESC) , print screen pause , the windows or start key ( Microsoft Windows logo) , and a shortcut key. The shortcut key has a mouse pointer printed on it and is used to access the options available by pressing the right mouse button.the ESC key cancel the selected option, and the pause key suspends a command / process in progress. Finally, the print screen key captures everything on the screen as an image . The image can be pasted into any document 

Define Computer? Explain what are different types of Computer.

Semester :-1

Unit:-1

Define Computer? Explain what are different types of Computer.
Ans:-
          Computer is an electronic device, which stores data, process it and gives the results consistently, accurately at very high speed according to our instructions. The word computer is derived from the word "Compute". It means perform or calculate. That's way, the computer is also called as calculating device. The computers can broadly classified into three types namely
 a) Analog Computers
b) Digital Computers
c) Hybrid Computers
a) Analog Computers:-
                                            The analog computer operate by measuring instead of counting. The analog computer works on the supply on continuous electrical signals. The display is also continuous and its output is in the form of graphs.
                In Analog Computer, the input data is a continuously changing electrical or non-electrical information. Computations are carried out with physical quantities such as Voltage, length, Current, Temperature etc. The device measuring such quantities are called analog devices. The advantages of analog computer is that all calculation take place in parallel and hence it is very fast. It is used for engineering and scientific application. But their accuracy is poor as compared to digital computer.
Characteristics :-  

1. It operates by measuring.
2. It requires by measuring.
3. It function on continuously quantity.
4. The output is usually represented in the form of graph.
5. The accuracy of the output is poor.
6. It has limited memory space.
7. It is not versatile i. e. It has limited applications.
8. Speed is very low.
9. These computers are not suitable for business and industry.
10. The calculations are first converted into equations and later converted into electrical signals.

b) Digital Computers :-

                                             As the name implies, the digital computer with quantities represented as digits. In digital computer, both numeric and non-numeric information are represented as string of digits.

             In Digital Computer, the input data is discrete in nature. It is represented by binary notation in the form of "0"s and" 1"s digital computers are much faster than analog computers and are more accurate. Digital computers are largely used for business and scientific applications.

              The basic operation performed by a digital computer is addition. Hence, the other operation such as multiplication, division, subtraction and exponentiation are first changed into "Addition and then compute".

Characteristics :-

1. It operates by Counting
2. It functions on discrete numbers
3. The calculations are converted into binary numbers
4. The output is represented in the form of discrete values
5. Its accuracy is good
6. It has large memory space
7. It is versatile in nature
8. It is suitable for a number of applications
9. It processing speed is high
10. It is highly suitable for business applications

c) Hybrid Computers :-

                                             The Hybrid Computers combines the features of both the analog and digital computers. These are used for special Analytical applications. weather-monitoring system and device used in Intensive Care units (ICU) of the hospitals are example of hybrid Computers.

                 Further more, computers are classified depending on the application as: special purpose Computers and General purpose Computers.

       As the name implies the special purpose computers are designed to perform a specific task or a special application. 

Explain various Computer Generations in detail.

Semester :-1

Unit:-1

Explain various Computer Generations in detail.

The Computer Generation means step-by-step growth in the technology. Originally, the term generation was used to distinguish between varying hardware technologies. But nowadays, it has been extended to include both the hardware and the software, which together make up an entire computer system.
                                  There are totally five generations of computer till today. Each generation will be discussed in detail. The following table illustrates the generations of computer hardware :
S. No. 
Generations of computers 
Components used 
Operating speed 

1.
First Generation 
Vacuum tubes
Milli Seconds 

2.
Second Generation 
Transisters
Micro Seconds 

3.
Third Generation 
Integrated Circuits (IC) (or) SSI (or) MSI
Nano Seconds 

4.
Fourth Generation 
Micro processors (or) LSI (or) VLSI
1 to 10 
Nano Seconds 

5.
Fifth Generation 
Ultra LSI
1 to  100 
Nano Seconds 


a) 1st Generation Computers (1942-1955) :-
                                                                           The magnetic relays of the very first computer were replaced by vacuum tubes. The computers which were made of these vacuum tubes came to be known as the first generation computers. The ENIAC computer made use of 18,000 vacuum tubes and relays. It was capable of performing 5,000 additions in one second. It was bulky in size and needed heavy air conditioning.
Advantages :

1. Vacuum tubes were the only electronic components available at that time.
2. This technology made possible the advent of electronic digital computers.
3. These computers were the fastest calculating device of their time.
4. These computers could perform computations in milli seconds.

Disadvantages :

1. Very big in size
2. Occupies large space
3. High heat production
4. High power consumption
5. High cost
6. NO reliability
7. Vulnerable to frequent hardware failure.
8. Limited Commercial use.
9. Need Constant maintenance.

b) 2nd Generation Computers (1955-1964) :
                                                                            The transistor was invented in 1948 at the Bell laboratories and was capable of performing all the functions of a vacuum tube at a much faster rate. It consumed little power and generated less heat. The computers which were working with transistor came to be known as the second generation computers. These computers were much smaller, consumed less power and generated little heat and were more reliable. These had capability of performing 20,000 to 50,000 additions per second.
Advantages :

1. Small in size
2. Better reliability
3. Computational time is micro seconds
4. Less heat generated
5. Better speed
6. Better portability
7. Less prone to hardware failure.

Disadvantages :

1. Frequent maintenance required
2. Need Air-conditioning
3. Manual Assembly of individual components into a functioning unit was required.
4. High cost
5. Commercial production was difficult.

c) 3rd Generation computers (1964-1975):
                                                                          The new techniques of small scale Integration (SSI) and medium scale Integration (MSI) led to the evolution of Integrated Circuit (IC). As many as few hundred transistor can be housed on a single Integrated Circuit. This chip can be as small as 4 to 8 square centimeters in the area and weight few grams. It consumes very little power and its cost is very low. The computers using the integrated circuit came to be known as third  generation computers. The first computer came from IBM and is called as IBM 360. These computers were small in size and Greater in capacity and performed as many as ten million additions per second.
Advantages :

1. Small in size
2. More reliability
3. Less heat generated
4. Computational time is Nano seconds.
5. Less hardware failure.
6. Low maintenance cost
7. Easily portable
8. General purpose computers.
9. Less power required
10. Commercial production was easier and cheaper.

Disadvantages :

1. Need Air-conditioning
2. Highly sophisticated technology required for the manufacture of IC chips.

d) 4th Generation Computers (1975-1989):
                                                                           The beginning of 1970s saw a totally new face in the computer industry with the introduction of microprocessor. These microprocessor comprised of many LSI (Large scale Integration) and VLSI (Very large scale Integration) circuits having all elements to process the data. These microprocessors have thousands of transistors in them. The computers making use of these microprocessors are known as fourth generation computers.
Advantages :

1. These computers were much more small in size.
2. Very cheap as compared with previous generation computers.
3. Consumed less power
4. Mainframe and super computers fall in this generation.
5. Having more reliability
6. Having less hardware failures.
7. They had large and faster primary and secondary storage.
8. These are the general purpose computers.
9. Object oriented languages are supported.

Disadvantages :
     1. Highly sophisticated technology required for the manufacture of LSI chips.
5th Generation Computers (1989-present) :
                                                                           The fifth generation computers have a new technology called Artificial Intelligence incorporated in them. The computers which were made of these Ultra large scale Integration (USING) came to be known as the fifth generation computers. These computers require new architecture, new memory organizations and new programming languages. These will be the computers that can learn and make decisions.
Advantages :

1. The super computers fall under this generation.
2. Portable PC's also fall under this generation.
3. These computers consumes less power than the predecessors.
4. More user friendly
5. Supports wide operating system environments.
6. Supports newer and powerful applications
7. Having much faster and large primary storage capacity
8. The price range are affordable and very close to human being.
9. Supports parallel programming.

What are the characteristics of a computer? Explain.

Semester :-1

Unit:-1

What are the characteristics of a computer? Explain.

The main and most important characteristics of computer are.

1. Speed
2. Accuracy
3. Diligence
4. Versatility
5. Power of Remembering
6. No. I. Q.
7. No feelings

a) speed :-

                   A computer is a very fast calculating device. It can perform in a few seconds the amount of work that a human being can do in an entire year.

While talking about the speed of a computer, we do not talk in terms of seconds or even milliseconds. A powerful computer is capable of performing about 3 to 4 million instructions per second.

b) Accuracy :-

                         The accuracy of a computer is consistently high and the degree of accuracy of a particular computer depends upon its design. Each and every calculation is performed with the same accuracy.

                 Errors can occur in a computer, but these are mainly due to human than technological weakness, that is, due to imprecise thinking by the programmer or due to inaccurate data.

c) Diligence :-

                       Unlike human beings, a computer is free from tiredness, lack of concentration etc., and hence can work for hours together without creating any error and without grumbling.

d) Versatility :-

                         Versatility is one of the most wonderful things about the computer. One moment, it is preparing the result of particular examination, the next moment it is busy preparing electricity bills, and in between, it may be helping an office secretary to trance an important letter in seconds. In other words, a computer is capable of performing almost any task provided that the task Can be reduced to a series of logical steps. 

e) power of Remembering :-

                                                  A computer can store and recall any amount of information because of its secondary storage capability. Every piece of information can be retained as long as desired by the user and can be recalled as and when required. A computer forgets or looses certain information only when it is asked to do so. So it is entirely upto the user to make a computer retain or forget a particular information. 

f) No. I. Q ( Intelligent Quotient) :-

                                                           A computer is not a magical device. It can only perform tasks that a human being can The difference is that it performs these tasks with unthinkable speed and accuracy It possesses no intelligence of its own. Its I. Q. Is zero, at least till today. It has to be told what to do and in what sequence. Hence, only the user can determine what tasks a computer will perform. A computer cannot take its own decisions in this regard. 

g) No feelings :-

                            Computer have no feelings because they are machines. Although men have succeeded in building a memory for the computer, but no computer possesses the equipment of a human heart. Based on our feelings, taste, knowledge, and experience, we often make certain judgments in our day to day life. But computers cannot make such judgment on their own. Their judgment is based  on the instruction given to them in the form of programs that are written by us.

Define computer? Explain in detail logical organization of digital computer with neat diagram.

Semester :-1

Unit:-1

Define computer? Explain in detail logical organization of digital computer with neat diagram.? 

INTRODUCTION :
                   Computer is a electronic device which stores data, process it, and gives the result consistently, accurately at very high speed according to our instruction. The word computer is derived from the word "compute". It means perform or calculate. So a powerful computer can handle 3 to 4 million instruction per second (MIPS)
Input unit :-
           It is used to send data or programs into computer. There are several kinds of input units are available, they are keywor, light pen, joystick, and mouse, etc.
CPU :-
     Cpu stands for central processing unit. This is the main and most important part of the computer it is made up of three units. They are

• Memory unit
• CU (control unit)
• ALU (Arithmetic and logical unit)

a) memory unit :-
               The function of the memory unit is to store data or programs or information in the format of "ON" and "OFF" states. Because computer is an electronic device which identifies either "ON" and "OFF" states. That's why, all the information or data or programs will be stored inside the computer in the form of "ON" And "OFF" states.
b) CU :-
       CU stand for control unit. This unit to control the overall units either internally (i.e. Memory and ALU) and externally (i.e. Input - output units) connected to computer.
c) ALU :-
               ALU stand for Arithmetic logical unit. It will perform the arithmetic and logical operations.

Block Diagram of Digital computer

Output unit :-
           This unit is used to take the final results. There are two kinds of output units. They are a) Soft copy Device, Ex: monitor and b) Hardcopy Device, Ex: printer, plotter.
      Softcopy device are used to prepare the softcopies (monitor output). Prepare softcopy is used for temporary reference and it will save the stationery and printing cost whereas the hard copy device are used to prepare the hardcopier (paper output). Prepared hardcopy is used for further reference and it will waste the stationary and printing costs for unnecessary output is taken.
Secondary Storage Devices :-
                         This unit is used to store large amounts of data permanently. There are several kinds of secondary storage devices. They are magnetic tapes, magnetic disks, CDs etc.
Peripheral Devices :-
                  Whose devices are connected CPU externally then those devices are called peripheral devices.
Input and output units are called as peripheral devices.