Computer fundamental notes (ccc) by social guide

 

         Computer Fundamental

 

A computer is an electronic machine which takes data as an input and processes it and provides output result in the form of meaningful information.

Input                    Processing                           Output

(Keyboard)          (Processor)                          (Monitor)

 

Input:-This is a process of entering data and program into the computer system.

 

Processor:-The task of performing operation like arithmetic and logical operation is called processor.

 

Output:-This is the process of producing result from the data or the instructions provided by the input device.

 

Data:- Raw facts are known as data.

 

Information:-Meaningful results /data are known as information.

 

 Instructions:-Command that tells computer what to do are called instruction.

 

Storage: -The process of saving data and instructions permanently is known as storage.

 

Soft copy:-These are the output which is being provided by the display on the screen.

For ex:-monitor, projector, CD.

 

Hard copy:-These are the output which is being provided on through the printer as an output.

For ex:-Printing paper.

 

Computer  meaning

Computer is an electronic data processing device which data input, accepts and stores data input, processes the and generates the output in a required format.

Note : Charles babbage is known as the father of computer .

 

Full form of computer :-

C =commonly

O =operating

M =machine

P =particularly

U =used for

T =technical and

E = educational

R =research

 

Characteristics of computer:-

1)   Speed

2)   Accuracy

3)   Versatility

4)   Diligence

5)   Automation

6)   Storage Capacity

7)   Reliability  

 

Speed:- Modern computer are operated at very high speed.

 Electrical pulses travel at incredibly speed because computer is an electronic device .Many of today’s computer can execute several million instructions in just one second. The speed of computer is calculated in mega hearts (MHz) that is one million instructions per second.

Accuracy:- The computer rarely makes a mistake or an error. If the data and instruction are filed into the computer correctly then it gives correct result.

Versatility:- Computer can handle a variety of application and jobs and can be used in various fields at a time.

Diligence:-A computer can performed a set of functions without getting tired or bored.

Automation:-No human intervention is required once the instruction and data gives the CPU follows these instruction until it meets the last instruction which says stop program execution.

Storage Capacity:- Computer can store a large amount of information. Today’s computer can be equipped with disk capable of storing almost any type of data such as picture, sound, graphics etc.

Reliability:-It means the measurement of the performance of the computer which is measure against some predefined standards for operation without any failure.

 

Limitation of Computer:-

 

·       It is not possible to communicate with computer using normal conversational language.

·       They possess limited intelligence.

·       They can’t take unstructured decision because of program software limitation.

·    It  has no intelligence to perform any task. A computer cannot take any decision.

·    It functions as per a user’s instruction, so it is fully dependent on human being.

·    Computers have no feelings or emotions.

·    It cannot learn from its past mistakes.

 

Application of computer

 

Insurance

Health Care

Military

Management

Marketing

Education

Banking

Hospital

Railway

Entertainment

Games

 

History of computer

Inventor	Year	Invention	Important features	Uses
China	16 century	abacus	The very first mechanical calculating device	Addition and subtraction operations
John napier	1617	Napier’s bone	Three dimensional structure marked with stripes and bones	Multiplication and division operations holding number from 0 to 9
Blaise pascal	1642	Pascaline /numerical wheel calculator	First mechanical and automatic calculator, designed with regards to pressure of liquid	Carry was introduced in this period
Charles babbage	Early1820	Difference engine	For calculation and printing of simple math tables	This machine can give accuracy of about 20 places after decimal.
Charles babbage	1833-1874	Analytical engine	First general purpose computer used to tabulate polynomial function	For salving complex mathematical problem this uses sign and magnitude for number’s representation.
Howard aiken	1944	Mark I	Used during a second world war	It consists of switches, counters and control circuits.
Jp Eckert and jw mauchly	1950	ENIAC (Electronic Numerical Integrator And Computer	First electronic digital computer	Discovered for weather forecasting
John von Neumann	1946-1952	EDSAC (Electronic Delay Storage Automatic Calculator)	Provide storage capacity	The first computer program was run on this machine
John von Neumann	1950	EDVAC (Electronic Discrete Variable Automatic Computer )	Binary computer	It consists of almost 6000 vacuum tubes,12000 diodes
Jp Eckert and jw mauchly	1951	Univac (universal automatic computer)	First general purpose electronic computer	It uses magnetic tape for both input and output

 

 

 

Generations of computer

 

First Generation(1945-1956):-

The period of first generation was 1945 to 1956. The computers of first generation used vacuum tubes. In this generation mainly batch processing operating system were used. Punched cards, paper tape, & magnetic tape were used as input and output devices. The computers in this generation used machine code as programming language.

 

Some computers of this generation- ENIAC, EDVAC, UNIVAC, IBM-701, IBM-650
EDVAC: electronic discrete variable automatic computer )first main frame computer)
UNIVAC:  Universal automatic computer(first commercial use computer)

1st electronic computer ENIAC (Electronic Numerical Integrator and Computer)

Second Generation(1956-1963):-

The period of second generation was 1956 to 1963. In this generation transistors were used. In this generation, magnetic cores were used as primary memory and magnetic tape and magnetic disks as secondary storage devices. In this generation assembly language and high-level programming languages like FORTRAN, COBOL was used. The computers used batch processing and multiprogramming operating system.

 

Some computers of this generation-

IBM 1620, IBM 7094, CDC 1604, CDC 3600, UNIVAC 1108

Third Generation(1964-1971):-(C language)

The period of third generation was 1964 to 1971. The computers of third generation used integrated circuits (IC's) in place of transistors. The IC was invented by Jack Kill . In this generation remote processing, time-sharing, multi-programming operating system were used. High-level languages (FORTRAN-II TO IV, COBOL, PASCAL PL/1, BASIC, ALGOL-68 etc.) were used during this generation.

Some computers of this generation- IBM-360 series, Honeywell-6000 series, PDP (Personal Data Processor), IBM-370/168, TDC-316

Note: All the high-level languages like C, C++, DBASE etc. were develop in this generation.

 

Fourth Generation(1971 to 1989):-

 

The period of fourth generation was 1971-1989.The computers of fourth generation used Very Large Scale Integrated (VLSI) circuits. Fourth generation computers became more powerful, compact, and reliable. In this generation time sharing, real time, networks, distributed operating system were used.

DEC 10 ,STAR 1000 , CRAY-1(Super Computer)

 

Fifth Generation(1989 to present):-(microprocessor)

 

The period of fifth generation is 1989-present. In the fifth generation, the VLSI technology became ULSI (Ultra Large Scale Integration) technology. This generation is based on parallel processing hardware and AI (Artificial Intelligence) software.  “The father of AI- John McCarthy”. All the high-level languages like C and C++, Java, .Net etc. are used in this generation. Note: in this generation use Pro-LOG language. (Prolog is a logic programming language)

Some computer types of this generation-Desktop, Laptop, Notebook...etc

                      Classification of Computers

 

 On the basis of work:-

 

·        Analog Computer:- Analog computer are used mostly in Medical Sciences. This kind of computer work on continuous data values for e.g. if you have to calculate the pressure or something similar the kind of technology having will be useful.

·      Digital computer: -A computer that performs calculations and

     logical operations with quantities represented as digits, usually in the        binary number system.

·       Hybrid computer:- This kind of computer comes with both characteristics(digital and analog) are called hybrid. This is used there where it needs  to calculate both the digital and analog data for e.g. in hospital (E.C.G Machine).

 

On the basic of size:-

 

1. Micro computers

2. Mini computers

3. Main frame computers

4.   Super computers

 

·       Micro Computer:- The processor is very small so that called Micro Processor and device is called Micro computer. Micro computer is single user device example: Desktop, Laptop, Notebook, PDA etc.  

·        Mini Computer:- The processor of Mini Computer is small but larger than Micro Processor .Minicomputer multi user device generally used in designing company for commercial use.

·     Mainframe computer:-It has larger processor and multiuser device. Number of users is more than Minicomputer. This is multiuser and multitasking device mostly used in Metrology.

·        Super Computer:- The processor is biggest than other computer and processing capacity is highest than other devices. It is multi user fastest calculating device generally used in nuclear science for calculation purpose. CRAY-I is the first supercomputer. India’s first supercomputer is PARAM-10000.

 

 

`Function of computer:-

 

A computer is designed to carry out five functions—

1.    Accepting the data and instruction as input.

2.    Storing the data and instruction in its memory and removing the some as and when required.

3.    Processing the data as per instruction to convert it into useful information.

4.    Communicating the information to user as output.

5.    Directing the manner and sequence in which the above operations are performed.

Basics of Hardware and Software

     Hardware is a physical parts computer that cause processing of data ,Software is a set of instruction that tells a computer exactly what to do _

     Hardware can not perform any task without software, software can not be executed .

following hardware components are available to perform various task

 Motherboard: It is the biggest electronic circuit board inside the computer system which holds the CPU, main memory and other parts, and has slots for expansion cards.

 SMPS (Switch Mode power supply): It converts the alternating current into direct current and provides current to the entire computer.

 Storage controllers: Storage controllers of IDE, SCSI or other type that control hard disk, floppy disk, CD-ROM and other drives: the controllers sit directly on the motherboard (on board) or an expansion cards.

 Graphics controller: It produces the output for the monitor. j) The hard disk, floppy disk and other drives for mass storage.

Interface controllers: Interface controllers (parallel, serial, USB, Firewire) to connect the computer to external peripheral devices such as printers or scanners.

 

Block diagram of computer system:-

 

 

 

 

 

 

 

1. Input unit

2. Memory unit

3. Arithmetic logic unit

4. Output unit

5. Control unit

..

 Input unit:-  it is use to input data into the computer system . some example input unit is mouse keyboard   light pen etc.

Memory unit:- It is use to store data for long time and for a short time

         It is divided into two types

1.                 Primary memory

2.                 Secondary memory

è  Primary memory is use to store data temporary time.

è  Secondary memory is use to store data for a long time.

ALU:- It is use to solve math and logical related problems.

Control unit:-  It is use to manage all unit of computer system.

Output unit :- it is use to display the result of data after the processing which is enter into the computer   system with the help of input unit.

Processing:- A process is the instance of a computer program that is being executed by one or many threads. It contains the program code and its activity.

Types of Processing :

There are mainly three types of processing

 Serial Processing- Execute one instruction at a time; Fetch, decode and execute. 

 Parallel Processing- Multiple processes are done at the same time, for example     Network Servers, Super Computers. 

 Pipelining Processing- It refers to overlapping operations by moving data or instructions into a conceptual pipe with all stages of the pipe performing simultaneously.  Pipelining does not reduce the time to complete an instruction, but increases the number of instructions that can be processed at once.

 

Computer language:-

It is  a medium by which we can share our thought feeling  to each other-

In computer there are 3 types of language

1.               High level

2.               Low level

3.               Assemble

 

High level :-

 it is also known as human language and it is not easy to understand by the computer system.

Low level :-

 It is also known as machine level language .

Assemble language:-

It is a collection of some symbol and code .

 

 

Input and output devices :-

 

Input devices:-

it  are used to communicate with the computer either by entering the data into computer.

Keyboard :- keyboard is the most common and very popular input device which helps in inputting data to the computer the layout of the keyboard is like that of typewriter .

Keyboard are of two sizes 84 keys or 101/102 keys, but now keyboards with 104 keys or 113 keys are available for windows

Types of keys in keyboard

1.  Typing keys- (a to z)

2.  Numeric keys-(0 to 9)

3.  Function keys-(f1 to f12)

4.  Control keys-(home ,end, ctrl, alt, esc, page up, page down, arrow keys)

5.  Special key- (enter, shift, caps lock ,num lock, tab and print screen.)

Mouse:- mouse is most popular pointing device. It is a very famous cursor control device. Generally it has two buttons called left and right button and a wheel is present between the buttons.

Joystick:-joystick is also pointing device which is used to move cursor position on a monitor screen. It is mainly used in computer added designing (cad) and playing computer games.

Light pen:-light pen is a pointing device which is similar to a pen. It is used to select a displayed menu item or draw pictures on the monitor screen.

Track ball: - track ball is an input device that is mostly used in notebook or laptop computer instead of a mouse.

Scanner: - scanner is an input device which works more like a photocopy machine. It is used when some information is available on a paper and it is to be transferred to the hard disk of the computer.

Digitizer: - digitizer is an input device which converts analog information into digital form. Digitizer is also known as tablet or graphics tablet.

Microphone: - microphone is an input device to input sound that is then stored in digital form.

Magnetic ink card reader/magnetic ink character recognition:- MICR is an a input device is generally used in banks because of a large number of cheques to be processed ever day.

Optical character reader (OCR):- OCR is an input device used to read a printed text. OCR scans text optically character by character converts them into a machine readable code and stores the text on the system memory.

Bar code readers (BCR):- bar code reader is a device used for reading bar coded data (data in form of light and dark lines). Bar code data is generally used in labeling goods, numbering the books etc.

Optical mark reader (OMR):- OMR is special type of optical scanner used to recognize the type of mark made by pen or pencil. It is specially used for checking the answer sheets of examinations having multiple choice questions.

Output devices:-

It  give result either in hard and soft form. The devices which are used to display the user either in the form of hard copy or soft copy are called output devices. The example of output devices are monitor, printer, plotter, projector, speaker etc.

Monitors:- monitors commonly called as visual display unit(vdu).this is an output device. This is an electronic visual display comprising of display device circuitry and an enclosure used to display the output. The picture on a monitor is made up of thousands of tiny colored dots called pixel.

             Types of Monitor

CRT (Cathode Ray Tube):- this is like television like screen where the results of a computer’s tasks are display. In this technology cathode ray falls on florescence screen and by deflecting rays make picture.

Monochrome: - Also called black and white.

Color:- it has three different phosphors which emit red, green, and blue light respectively and due to the color picture appears in colored view.                                                                                                                                                                                                         

LCD (Liquid Crystal Display):- this VDU is thin flat and having light modulating technology.

TFT (Thin Film Transistor ):- it is a variant of LCD makes matrix but not self lighting .

LED (Light Emitting Diode):- it is self back light emitting technology picture quality is better.

 

Projector:- projector is output device and often used in meetings presentations. it contains a lens inside which is used to flash the film to an object.

Plotter:-plotter is an output device that is used to produce graphical output on papers. Plotter is used to print the maps and architecture of infrastructure. It is used in the engineering applications.

Speaker:- speakers are also kind of output devices which is used to play a sound as output.

Printer:-  printer is an output device that prints text documents, images, spread sheet etc. as hard copy. Printer quality is measured in dot per inch (DPI).

There are two types of printers

1.   Impact printer

2.   Non-impact printer

Impact printer:- the impact printers print the characters by striking them on the ribbon which is then pressed on the paper.

Types:-

Dot matrix printer :- There is a metallic or plastic head having pins(9 pins or 24 pin head in dot matrix).it creates characters by striking pins against ink ribbons.

 

Daisy wheel:- head is lying on a wheel and pins corresponding to characters are like petals of daisy (flower name) that is why it is called daisy wheel printer.

 

Drum printer:- this printer is like a drum in shapes so it is called drum printer.

 

Chain printer:- it prints one entire line text before advancing to  another line .

Non impact printers: - non impact printer prints the characters without using ribbon. These printers print a complete page at a time so they are also called as page printer.

Types :-

laser printer:- in this technology as paper passes the through the printer, the laser beam fall at the surface of a cylindrical drum called a photoreceptor. this drum has an electrical positive charge by reversing the charge in certain areas of the drum the laser beam print patterns (such as text and image) onto the photoreceptor.

 

inkjet printer:- They print characters by spraying small drops of ink onto paper. These printers produce high quality printings. Color printing is also possible.

 

 

         Computer memory

A memory is just like a human brain. It is used to store data and instruction. Computer memory is the external and internal storage area.

 The memory of the computer is divided into two categories:
1.Primary Memory
2.Secondary Memory

Primary Memory (main memory):-
this is the main memory of the computer. CPU can directly read or write on this memory. It is fixed on the motherboard of the computer.

Primary memory is further divided in two types:
1.RAM(Random Access Memory)
2.ROM(Read Only Memory)

 

RAM (Random Access Memory):-
RAM is a temporary memory. The information stored in this memory is lost as the power supply to the computer is turned off. That’s why it is also called Volatile Memory. It stores the data and instruction given by the user and also the results produced by the computer temporarily.

 

Type of RAM :-

                     i.        SRAM :-(STATIC RANDOM ACCESS MEMORY) it can store without any need of frequent refreshing .

                    ii.        DRAM :-(DYNAMIC RANDOM ACCESS MEMORY) it uses capacitor to store data . it require regular refreshing.

                   iii.        SDRAM :-(SYNCHRONOUS DYNAMIC RANDOM ACCESS MEMORY) A new type of DRAM  that can run at much higher clock speed than conventional .it actually synchronizes itself with CPU .

ROM (Read Only Memory):-
Information stored in ROM is permanent in nature. It holds the data even if the system is switched off. It holds the starting instructions for the computer. ROM cannot be overwritten by the computer. It is also called Non-Volatile Memory.

 

Types of ROM

     i.        PROM: Programmable Read Only Memory (PROM) which can be written only once .it is manufactured as blank memory .

    ii.        EPROM : Erasable Programmable Read Only Memory Users can delete the data of EPROM thorough pass on ultraviolet light and it erases chip is reprogrammed.

   iii.        EEPROM: Electrically Erasable Programmable Read Only Memory similar to the EPROM but it uses electrical beam for erase the data of ROM. (flash ROM).

 

 

Secondary Memory (auxiliary memory):-

this memory is permanent in nature. It is used to store the different programs and the information permanently (which were temporarily stored in RAM). It holds the information till we erase it.

 

Different types of secondary storage devices are:

Magnetic Tape, Floppy disk, Hard Disk, Compact Disc, DVD, Pen Drive, Flash Drive, etc.

Magnetic tapes:-

Magnetic tape is a plastic tape which contains information in a sequential form. This tape contains a metallic polish layer known as iron oxide which is used to store magnetized the particles. The width of the ribbon also varies from 4mm-1 inch.

 

Floppy disk:-

It is 3.5 inch floppy is 1.44 megabytes. It is cheaper than any other storage device and is portable.

 

Hard Disk:-
This is the main storage device of the computer which is fixed inside the CPU box. Its storage capacity is very high that varies from 80 GB to 4 TB. A hard disc contains a number of metallic discs which are called platters.

Information is recorded on the surface of the platters in a series of concentric circles. These circles are called Tracks. For the purpose of addressing information.

Compact Disc (CD):-
This is an optical storage device with a storage capacity of up to 700 MB and it can store varieties of data like pictures, sounds, movies, texts, etc.

 

CD-ROM
CD-ROM refers to Compact Disc-Read Only Memory. Data or information is recorded at the time of manufacturing and it can only be read. A CD-ROM cannot be used to record fresh data by the computer.

CD-R
CD-R is the short form of Compact Disk-Recordable. Data can be written on it once and can be read whenever required. The data written once cannot be erased.

CD-RW
CD-RW stands for Compact Disk Re-writable. CD-RW can be used to write information over and over again, i.e, previous information can be erased and new information can be written on it using a CD writer fixed inside the CPU box.

DVD (Digital versatile disc):-
DVD stands for Digital Versatile Disk. it is an optical storage device which reads data faster than a CD.DVD can store data up to 4.7 GB . DVDs look just like CDs, they can hold much more data, for example, a full length movie.

 

Blue-ray Disc (BD):-
This is a newly invented optical data storage device whose storage capacity can be form  25 GB. it is mainly used to store high quality sound and movie data.

 

Flash Drive or pen drive or thumb drive:-
It is an electronic memory device popularly known as pen drive in which data can be stored permanently and erased when not needed.

1 nibble = 4 bits…

Hardware:-

It is  a device which we can touch and see.

In computer system mouse , keyboard, monitor are the example of the hardware device.

 

Software:-

it is a collection of program which is use to solve out any types of problem such as –

Ms office, tally, coral draw, and adobe Photoshop etc.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Types of software:-

There are two types of software—

1.           System software

2.            Application software

 

 

System software:-

It  is collection of programs designed to operate, control, and extend the processing capabilities of the computer itself. It serves as the interface between hardware and the end users.

 

Operating system:-

It is an essential component of a computer system which manages the resources of the system. It is a set of large and complex programs that acts as an interface between computer hardware and its users.

          

Category of operating system:-

 

There are two category of operating system are as:-

1.    CUI(CHARACTER USER INTERFACE)

2.    GUI(GRAPHICAL USER INTERFACE)

 

·       CUI:-In CUI all the operations are performed by commands. That is why such type of operating system is known as command driven operating system. For example:-MS-DOS, UNIX, etc.

·       GUI:-In GUI all the operations are performed by the means of graphical user interface .That is a platform which is operated by icons and events. For example:-WINDOW XP, WINDOW 7, WINDOW8, etc.

 

Utilities  software:- Utility programs are a collection of program that asset the user in performing in routine task and system maintenance task these  program or system utilities  is used to speed up and simplify the user of a computer and improve program efficiency.

     Open source s/w:- it is free & openly available to everyone       the code can be copied , modified or deleted  by users  &  organization.

    Proprietary  s/w:- it also known as “closed source software ” is non free computer software  for which the software’s publisher and usually copyright of the source code.

 

Translator:-Program that translates a program written in any computer language in to machine language code are known as translator. 

·       Assembler

·       Compiler

·       Interpreter

 

Assembler:- An Assembly language program can’t be directly executed by a computer.

It has to be converted into machine language. An assembler is a program that translates a program written in Assembly language into a machine executable code.

 

Compiler:- compiler is the translator that translates high level language program into, machine code and this machine code is executed.

 

Interpreter:- Interpreter are used to translate high level language  program line by line and executing each of the instruction  alternately.

 

 

 

 

                                                                                                                                                                                                                                                              

Application software:- it is install by user into the computer for his private use.

 Such as- ms office , tally , coral draw etc.

 

           Divided into two category:-

·       Standard Application software

·       Customized Application software

 

Standard Application software:-it  is set of programs used to deal with a particular application. This software is normally developed by a specialist software developer to solve common problems faced by many users.

For ex- MS-word…etc

 

Customized Application software:-it  is programs written by the user or programmer in order to perform specific job for the user. They are written in a variety of programming language is depending on the task.

For ex- Tally…etc

 

Mobile Application:-

It is most commonly used as an app ,is type of application software designed to run on a mobile or touch screen such as smart phone and tablet.

   

Types of apps

     i.        Native app

   ii.        Web app

 iii.        Hybrid app

Native app:-it is a software which  is used only for particular platform and not for other platform.

For ex- istore for iphone , playstore for android …etc

            Web app:-it is software that is stored on a remote server and delivered over the internet  through a browser interface.these apps redirect a user to URL.

For ex- html ,css ,javascript…etc

 

     Hybrid app:-it is build for multi platform web technology .

For ex- facebook , amazon …etc

 

                               Number system

Our computer system understand only 0&1 language that is also known as binary language.

 

There are four types of number system-

 

1.  Decimal number:-

     Range (0 to9 ) & base 10

     Ex:- (578)_{10 (}450)₁₀

 

2.  Binary number :-

     Range (0 to 1 ) & base 2

     Ex:-(1101010)₂ ,(101010001)₂

 

3.  Octal  number :-

     Range (0 to 7 ) & base 8.

     Ex:- (457)₈, (123)₈

4.  Hexadecimal number:-

      Range (0 to15 ) & base 16

      A=10,B=11, C=12, D=13, E=14, F=15

      Ex:- (258D)₁₆(158AB)₁₆