1. STORAGE IN COMPUTER By- Upendra Sharma

2. STORAGE DEVICE We can use storage device to save data in computer. It is divided in two parts- 1. Primary memory 2. Secondary memory

3. PRIMARY MEMORY It is made by electronic circuit. It store data when power supply is on. When power supply is switched off then data is lose. We can divide of primary memory in two parts – 1. Ram (random access memory) 2. Rom (read only memory)

4. RAM Ram is main memory of computer. It is a volatile memory. It is a read writeable memory. It store information when power supply is on. When power supply is off its loss our contain. It has two important type-: 1. Static Ram 2. Dynamic Ram

5. Static & dynamic Ram Static ram store information when power supply is switched on. And dynamic ram store information for few time. After some time dynamic ram loss her conten whenever power supply is on Dynamic ram is cheap rather then static ram.

7. ROM Rom is a permanent memory of a computer. Its don’t loss his contain when power supply is off. A normally user can not write and edit in Rom. It content write at manufacturing time by a programmer. It store basic application of computer.

8. Cont…….. Rom is comes in different type:- 1. PROM 2. EPROM 3. EEPROM In EEPROM we can erase information also and write it.

9. SECONDARY STORAGE Secondary storage is use to mass storage of data. Its storage is nonvolatile storage device. Its don’t loss our contain when power is off like main memory. We can store system software, compilers, and many important files is in this.

10. Namely it is:- Hard disk Floppy disk Magnetic tape CD ( compact disk) DVD (digital video disk) Pen drive SD card

11. HARD DISK A hard disk is a device used for mass storage of data. It is contained in a dust free environment. It store information as a faster rate. It has 4 platter for storing of data divided in track and sectors. The larger disk are use in main frame and the smaller disk in PCs.

14. FLOPPY DISK A floppy disk is use to storage of data. It is use magnetic tape to store data. It is a flexible devise so it called floppy. It is a good medium of data transfer in one computer to other computer.

15. COMPACT DISK(CD) It is an read and write memory. It is a disk made by resin, such as a polycarbonate. It a coated with a material whiche will change is reflecting property. The coating material highly reflecting usually aluminum. A high intensity laser beam form a tinny pit along a trace to represent 1, and a surface without a pit know as land represent 0.

16. DIGITAL VIDEO DISK(DVD) A DVD is introduced Sony in 1995. It is storage device looks kike a CD. A CD is same dimensions as a standard CD but cannot be read a CD player. But a DVD player can read standard CDs. A DVD store up to 4.7GB of data. A DVD drive a optical drive that combine CD and DVD writer.

17. PEN DRIVE It is also knows as thumb drive and flash drive. It can be connected in a USB port of a computer. The main component of a pen drive is flash memory. It is a west medium of transferring data one computer to another computer. Its storage capacity 4GB,8 GB, 16 GB 64 GB and more.

18. MAGNETIC TAPE Magnetic tape is a west medium for large volume of data. The tape is plastic ribbon usually ½ inch wide that coated one side with the iron oxide which is magnetized. The tape ribbon itself it store in reel 50-2400 feet. The magnetic tape can be erased and reuse again and again.

19. SD card (secure digital card) SD card is basically second generation multimedia card. The locking switch on this card prevent data from being read, written and deleted from the storage card. The storage card are available in two variant:- Mini SD card Micro SD card