Hardware

                      Hardware Hardware 

Any electronic mechanical or electromagnetic device that make up a computer is known as hardware. All the physical component of computer system is called hardware. For example CPU disk drive keyboard etc.

Computer hardware is divided into three parts.  

1. Input Unit
2. Central Processing Unit
3. Output Unit

1-Input Unit:- Input unit is used to to take input (data, information and instruction)from user. Some of the major input devices are as follows.

1-Keyboard

2-Mouse

3-Joy stick

4-Light Pen

5-Scanner etc. 

1-Keyboard:- Keyboard is the most important input unit of the computer. It is used to input data and instructions into the computer. The keyboard can have 101 or more keys. The keyboard keys can be divided into three parts.

I-Alphabetic key:- The total number of alphabets is 26 (A to Z). These keys are located in the middle                                   of the keyboard. These are used to input the alphabet.

II-Numeric Key:- The total number of numeric is 10 (from 0 to 9). These are located in two places on                                the keyboard. Used to input the numbers.

III-Special character key:- These keys are used to input special symbols (#,@,+,(,),",*,:,,; etc.).

IV-Arrow key:-The total number of arrows is 4. It is used to move the arrow in four different                                           directions. These are located in two places on the keyboard.

V-Special Key:- These keys are used to perform special tasks. Some of the major special keys are as                                 follows. Enter, Caps lock, Backspace, Tab, Delete, Escape, Alt, Ctrl, Insert etc. 

VI-Function key:- The use of the function key is different in different software. Tomorrow number is 12 (F1 to F12). It is located on the first row of the keyboard. 

 2-Mouse:- Mouse was invented in 1977 by Stanford Laboratory scientist "Douglas Engelbart".. It is used in graphical user interface based operating systems. I have two or three buttons. It is used to control the head. With its help, actions like click, double click, right click, dragon drop etc. are done. It is also called pointing device. There are three types of mouse.

1-Mechanical Mouse
2-optical mouse
3-cordless mouse

 3-Joystick:- This is also an input device. It has a handle that can be rotated 360 degrees. It also has buttons by which to operate the joystick. It is used to play games.

4-Trackball:- In this the hair is fixed on the upper surface. It is rotated with the thumb and the fingers are on the button, it is used mostly in laptops.

 5-Light pen:- It is a pointing device which is used like a mouse to control the pointer on the screen. There is a pad in it and there is a pen, when the pen is run on the pad, the pointer rotates. It is used to create pictures, figures and signatures on the computer.

6-Scanner:- Scanner is used to store any document or picture available on the paper in digital form in the computer's memory. The scanner stores the document electronically in the computer's memory.

7-Optical Mark Reader:- Optical Mark Reader is also called OMR. It is used to check the presence or absence of a pencil or pen mark on the paper. It is mainly used in the evaluation of answer sheets.

8-Bar Code Reader:- Bar code reader is used to read the code printed on the packet of a commercial product. It provides information related to the product. It is used in shopping malls and shops in big cities.

9-Magnetic Ink Character Reader:- Magnetic Ink Character Reader is also called M.I0C.R0 in short. It is used to read any special type of ink on checks and drafts. It is mainly used in banks.

10-Webcam:- Web camera is mainly used for taking pictures or making videos. Nowadays it is mainly used in video chatting.

 2-Central Processing Unit:- The Central Processing Unit is the most important unit of the computer. Through this all the parts of the computer are operated and controlled. The efficiency, working speed and efficiency of a computer system all depend on the CPU itself.

The main reasons for CPU are as follows.
1- To operate and control all the parts of the computer.
2- Processing the data.
3- To control the movement of data between different parts of the computer.
Computer CPU can be divided into three parts.
1-Arithmetical Logical Unit
2-Control Unit
3-Register

1-Arithmetical Logical Unit:- The function of Arithmetical Logical Unit is to perform all kinds of mathematical calculations and logical operations in the computer system. It performs all kinds of mathematical operations and logical operations. The data stored by the primary memory is sent to the ALU and after the operation, it is sent back to the memory.

2-Control Unit:- All the activities being done by the computer system and its hardware are operated and controlled by this part. The control unit also performs the task of reading and executing the instructions stored in the storage unit, receiving and operating the data from the input unit and passing the result after processing to the output unit.

23-Register:- Registers are small circuits of high speed. Register is used to temporarily store the results obtained after numerical and logical operations.

Memory :- The part of the computer that is used to store data and files. The lowest unit of storing data in a computer is called a bit. The main units of measurement of memory are as follows.

1 Bit = Binary Digit (0 or 1)
8 Bits=1 Byte
1024 bytes = 1 Kilo Byte
1024 Kilobytes = 1 Mega Byte
1024 Mega Bytes = 1 Giga Byte
1024 Gigabytes = 1 Terra Byte
1024 Terra Bytes = 1 Pete Bites

Computer memory can be divided into two parts.
1-primary memory
2-secondary memory

1-Primary Memory:- Primary memory is also called main memory or internal memory. The data and programs being executed by the CPU are stored in this memory. Primary memory has less storage capacity but higher speed. Primary memory can be divided into the following two parts.
1-RAM
2-ROM
1-RAM: - This is a temporary memory and when the computer is turned off, the information stored in it is destroyed. After the execution of the program by the CPU, the new data is loaded into RAM by deleting the data stored in RAM. There are two types of RAM:

A-Dynamic RAM

B-Static RAM

A-Dynamic RAM:- The information written in Dynamic RAM has to be rewritten after a few milliseconds otherwise it gets expired. The speed of this RAM is high but the storage capacity is less.

B- Static RAM: - There is no need to write the information stored in it again and again. The information is stored as long as the electric current continues to flow. The storage capacity of this RAM is low but the speed is high. This RAM is more expensive than static.

Read Only Memory:- It is happening in such a way in which the written information can be read only, in which neither new information can be written nor the written information can be changed. Or there is permanent memory, the information written in it does not end even after the computer is turned off. The information stored in the ROM is called BIAS (Basic Input Output System BIOS).
There are three types of ROM.
A-PROM(PROGRAMMABLE READ ONLY MEMORY)

B-EPROM(erasable programmable read only memory)

C-EEPROM(electrically erasable programmable read only memory)  

 A-PROM(PROGRAMMABLE READ ONLY MEMORY):- Music program once in PROM can neither be changed nor removed.

B-EPROM (erasable programmable read only memory):- Program stored in EPROM can be erased with the help of ultraviolet rays and can store new programs in it by reuse.

C-EEPROM (electrically erasable programmable read only memory):- Programs stored in EEPROM can also be changed, in this RAM, electrical method is used to erase the music program.

2-Secondary memory:- Secondary memory is also called auxiliary memory or external memory. Secondary memory is cheaper than primary memory and has more storage capacity. Secondary memory is used to store information temporarily. Some of the major secondary memory devices are as follows.

A-magnetic tape
B-floppy disk
C-Hard Disk
D-compact disc
E-Pan Drive
F-memory card

A-Magnetic tape:- Magnetic tape is a device of a rectangular structure. In this, hundreds feet long green coloured magnetic tape is used. This tape is coated with ferrous oxide. Both read/write operations can be done on it. A magnetic tape drive is used to read data from it. Its use is in very limited quantity.

2-Floppy Disk:- Floppy disk is a square thin and light in weight storage issue. Its data storage capacity can range from 100 KB to 2 MB. A floppy disk drive is required to read/write data on it. Presently it is being used sparingly.

From the point of view of size, there are two types of floppy :-
Floppy Disk

1- 5½ Diameter

2- Floppy Disk with a diameter of 23½

Floppy Disk 1- 5½ diameter: - It was invented in the year 1976 and it is also protected by plastic jacket. Its storage capacity varies from 360 KB to 2.44 MB.

Floppy Disk 2- 3½ diameter: - It was first used in Apple computer. Which is smaller than the previous floppy. Its storage capacity varies from 310 KB to 2.88 MB.

3-Hard Disk:- Hard disk is the most important unit used in computer storage. It is also called a fixed disk because it is permanently mounted inside the CPU. In a hard disk, several circular plates are connected at the same distance, data is stored on both surfaces of these plates. For each power there is a separate read write head that performs the task of writing and reading the data on that surface. The storage capacity of hard disk ranges from GB to TB.

4-Optical Disk: - is a flat, circular polycarbonate disc, on which data is stored in the form of pits inside a flat surface, in which data is stored by optical. There are two types of optical disc. of happens. 1-CD 2-DVD

1-CD:- First of all, let's talk about CD, we also call CD by the name of compact disc, it is such an optical medium that saves our digital data. There was a time when we used to use reeled cassettes, the invention of CD completely killed the cassettes in the market. About 700 MB of data can be saved in a standard CD. The data in a CD is saved in the form of a dot, in fact the laser sensor installed in the CD drive reads the reflected light from the CD's dot and creates an image in our device.

2-DVD:- DVD means Digital Versatile Disc, DVD was started after CD, although both CD and DVD look the same, but there is a difference in their data capacity, more data can be saved in DVD than CD. could. Meaning the user can save data from about 4.7 GB to 17 GB in DVD. After the advent of DVD, there was a huge decrease in the demand for CDs in the market.

5-Pen Drive: - It is known as Flash Drive, nowadays most Flash Drive is used to store data, it is an external device which is used separately in the computer. | It is also very small and light in size, Store data can also be read in it and it can also be improved. Flash Drive has a small Pried Circuit Board which is covered with a plastic or metal cover so it is strong. This is a Plug-and-Play tool. Today it is normally available in capacities like 2 GB, 4 GB, 8 GB, 16 GB, 32 GB, 64 GB, 128 GB etc.

6-Memory Card:- Memory card is used to store data in camera, mobile, and computer. Its storage capacity can range from 1GB to 32GB.

Output Unit:-The output unit is used to display data and results.
Output units are used to display data and results. Some of the major output devices are as follows.
1-monitor
2-Printer
3-plotter
4-speaker

1-Monitor:- Monitor is a major output device. It is also called computer screen or visual display unit. The data displayed on it can be seen. Display is the process of showing the output on the screen or monitor. Any shape on a monitor is made up of tiny dots called pixels. These pixels are arranged in the form of rows and columns in the monitor. It is also called visual display unit. It looks like a TV. Monitor is one of the most important output device.

Without it the computer is incomplete. It displays the output as a soft copy on its screen.
Monitor classification by colour
 1-monochrome monitor
2-Grey-Scale monitor
3-Color Monitor

1-Monochrome: - This word is made up of two words mono meaning single and chrome meaning colour, so it is called Single Colour Display and it shows the monitor output as Black & - Displays as.

2-Gray-Scale:- These monitors are similar to monochrome but it displays any type of display (Gary Shades), this type of monitor is mostly handy computer like laptop. ) are used.

3-Color Monitors:- Such a monitor displays the output in the form of adjustment of RGB (Red-Green-Blue) radiations due to the principle such monitors are able to display graphics in high resolution. are capable. According to the capacity of the computer memory, such monitors have the ability to display output in colours ranging from 16 to 16 lakhs.

Classification of monitors by technology

1-CRT Monitor

2-LCD (Liquid Crystal Display)

3-LED ( Light Emitting Diode)

1-CRT Monitor:- The most commonly used Output Device is also called VDU (Visual Display Unit), its main part is cathode Ray Tube which is generally called Picture Tube. Most of the monitors have picture tube element which is used for TV. This tube is similar to the set CRT This technology is called cheap and provides output in perfect colour. CRT has electron gun which emits a beam of electrons and cathode rays. This electron beam is passed from electronic grid to reduce the speed of electrons on CRT monitor. Phosphorus is coding, so as soon as the electronic beam hits the screen, the pixels start shining and the image appears on the screen.

2-LCD (Liquid Crystal Display): - Liquid Crystal Display is also known as LCD, it is a digital technology that creates a shape through a liquid crystal on a flat surface, it takes less space, it takes less energy and than traditional Cathode ray tube produces relatively less heat than the monitor, this display was first used in laptops, but now this screen is also being used for desktop computers.

2-Printer:- Printer is used to print data and information on paper. The information displayed on the printer is called hard copy. On the basis of technology there are two types of printers.

1-Impact Printer

2-Non Impact Printer

1-Impact Printer:- Impact printers are those printers in which there is contact between the print head and the paper. To print each character, the print head hits the paper. It uses a metal hammer as the print head that strikes the ribbon on the paper. Due to this collision the shape of the printhead is printed on the paper. The following printers come under the category of impact printers.

1. DOT MATRIX PRINTER
2. DAISY WHEEL PRINTER
3. LINE PRINTER
4. CHAIN ​​PRINTER
5. DRUM PRINTER

2-Non-Impact Printer(Non-Impact Printer):- Those printers in which there is no contact between printhead and paper are called non-impact printers. Non-impact printers will have high level of printing quality. The following printers come under the category of non-impact printers.

1. LASER PRINTER
2. INKJET PRINTER
3. MULTI FUNCTION PRINTER
4. THERMAL PRINTER

                Major Printers

1-Dot Matrix Printer (Dot Matrix Printer):- This printer is an impact printer. The printer head of this printer has a sole of many three, which when each pin touches the ribbon and the paper prints a stop. group occurs. The pin printheads of one column at a time come out and print a scold so that a character is formed in several steps and the print progresses in the direction of the line. The speed of dot matrix printers can range from 30 to 600 characters per second. The printing quality of this printer is not good.

2-Daisy Wheel Printer(Daisy Wheel Printer):- It is an impact printer with solid currency letter. The shape of its print-head is similar to that of a daisy flower, hence it is called Daisy Wheel Printer. This printer prints high quality printouts but its speed is slow. The printhead consists of a circle whose spokes of a solid spoke of a character while rotate the print position and strike the paper with a hammer on top of the ribbon to print a character.

3-Line Printer:- Line printer is also an impact printer. It is used in large size computers. Its speed is very high. It can print 300 to 3000 lines in a minute. These tenders are used in mini and mainframe computers. The following three printers come under the category of line printers.

1. drum printer
2. chain printer
3. band printer

4-Laser Printer (Laser Printer):- Laser Printer is a non-impact printer. Dry ink is used to print in this printer. This printer also uses dots to print. These dots are very small and close enough to provide very clear print quality. 300 to 600 D.P.I. Up to or more reservations can be printed. The quality of the inventor is very good. Both colour and black and white prints can be taken using them.

5- Inkjet printer (inkjet printer):- Inkjet printer is also a non-impact printer. In this, characters and graphics are printed by spraying drops of ink on the paper by a nozzle. The output of this printer is very clear because the letter formation in it consists of many teeth. The print quality of this printer is usually 300 dot per inch.

3-Plotter:- Plotter is also a major output unit. It is used to print pictures. Plaster is used for making maps, graphs and printing. There are two types of plotters.

1. Drum Pen Plotter
2. Flatbed Plotter

A-Drum pen plotter:- This is a plotter in which a pen is used to make a shape. With the help of a pen, drawings are made on the paper, in this device the paper is mounted on a drum which is slowly moved and prints 10.

B-Flatbed Plotter (Flat Plotter):- In this, the paper is placed in a stationary state on the Edward or tray. In this, a pan is kept on one arm, which makes a picture by moving up and down on the paper from the motor left and right, in which the pen is controlled from the computer.