Which one is the magnetic and optical memory?
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In a computer system, several types of secondary storage devices like HDD, CD, DVD, etc. are used to store permanent data and information. These devices can be categorized into two types namely – magnetic memory and optical memory. Show
A magnetic memory like HDD consists of circular disks made up of non-magnetic materials and coated with a thin layer of magnetic material in which data is stored. On the other hand, optical disks are made up of plastic and consist of layers of photo-sensitive materials in which the data is stored using optical effects. A major advantage of the magnetic disk and optical disk is that they are inexpensive storage devices. What is a Magnetic Disk?A Magnetic Disk is a storage device and uses magnetization process for data processing like read/write/access operations. Magnetic disks have circular platters coated with magnetic material. The platters are made up of non-magnetic materials like aluminium and its alloys. These disks are placed inside a rotary drive where the magnetized surface of the disk rotates close to read-write head, where the read-write head is a device consists of a magnetizing coil and a magnetic yoke. The readwrite head produces a magnetic field based on instruction to store or delete the data on the disk. Data is stored in form of tracks, spots and sectors. Examples of Magnetic disks include hard disks, floppy disks, magnetic tapes, etc. What is an Optical Disk?Optical Disk is again a storage device and use optical storage technology for data processing like read/write/access operations. An optical disk stores data using laser light and is read using the same. Laser light reads data on a spinning disk. Optical disks are also used as the permanent storage device in computers. An optical disk is made up of a resin like polycarbonate, and the digital data and information is stored in the polycarbonate surface in the form of microscopic pits. Then, the microscopic pitted surface is polished with a highly reflective substance. Also, in order to protect the disk from scratches, it is coated by acrylic. The data is read and write on the disk through a low-powered laser beam housed in an optical disk player. Examples of optical disks include CD, DVD, Blue Ray Disk, etc. The following table compares and contrasts all the important features of Magnetic Disks and Optical Disks − ParameterMagnetic DiskOptical DiskMedia TypeMagnetic disk are fixed storage media.Optical disks are portable storage media.Signal To Noise RatioMagnetic disks have intermediate S/N ratioOptical disks have excellent S/N ratio.Sampling RateThe sampling rate of magnetic disks is low.The sampling rate of optical disks is high.UsageMagnetic disks are commonly used where random access is needed.Optical disks are used where a regular data streaming is needed.Track StructureMagnetic disks have circular track structure.Optical disks have spiral track structure.Data AccessHard Disk, Floppy Disk, Magnetic Tape, etc. are examples of magnetic disksCD, DVD, Blu-ray, etc., are the examples of optical disks.ReuseMagnetic disks are highly reusable and used for random read/write operations.Most of the optical disks are readonly once written.CostMagnetic disks are costly per MB.Optical disks are cheaper per MB.ConclusionThe most significant difference between a Magnetic Disk and an Optical Disk is that a magnetic disk stores the data using magnetic field, while an optical disk uses photo-sensitive materials and effects of light (laser light) to store the data. If you are unable to see the table.Then, copy it and paste it into microsoft word. Magnetic Storage Optical Storage a) Stores data in magnetic form. b) It is affected by magnetic field. c) It has high storage capacity. e) It doesn't use laser to read/write data. f) Magnetic storage devices are ; Hard disk , Floppy disk, Magnetic tape etc. a) Stores data optically & used laser to read/write. b) It is not affected by magnetic field. c) It has less storage than hard disk. e) Data accessing is high as compared to floppy. f) Optical storage devices are ; CD-ROM,CD-R, CD-RW, DVD etc. Optical Storages used to be incredibly popular up until the last couple of years where cloud storage and the rise of video and game streaming services have massively reduced their popularity. Types of optical storage devices:
Optical storage devices offer cheap and portable high capacity secondary storage. Far more portable than an internal hard-drive, which makes them good for small / medium size backups and great for sending through the post. How they workOptical storage devices work by firing a laser at the surface of a spinning disk. The disc is covered in a pattern of pits in the CD surface. As the laser hits the pits it is reflected and the pattern of pits it detected by a laser detector. Solid State StorageSolid State Storage Devices SSD Drive – Expensive but fast Solid-State-Devices-Revision-Sheet Solid state devices are the newest form of storage to emerge. The technology is used in Hard Drives, SD Cards and USB sticks. Solid state storage devices work by storing data in flash chips electronically. They are still more expensive than traditional storage devices but the price per GB is falling all the time. Advantages
Disadvantages
Very portable and small – but needs a reader to use CharacteristicsCommon Storage Device ComparisonsDevice TypeCapacitySpeedPortabilityDurabilityReliabilityCostMagnetic Hard Drive HDDHigh Capacity(2TB +)Relatively Slow Read / Write SpeedsNot very portable and quite heavyLong life span, but susceptible to damage / data corruption if droppedVery ReliableCheapest form of main secondary storageSolid State Hard DriveMedium Capacity <1TBExceptionally fast read / write speedsMore portable than HDD but not as portable as other types, as usually inside the pcNo moving parts, so very durableQuite reliable, up to 5 years.Twice the price of HDD DrivesSD CardLow / Medium Capacity <256GBVery fast read / write, as flash memoryExtremely portableWon’t be damaged if dropped, but easy to lose and susceptible to water damageNot very reliable, prone to stop working over timeQuite high cost per GBPen DriveLow / Medium Capacity <256GBVery fast read / write, as flash memoryExtremely portableWon’t be damaged if dropped, but easy to lose and susceptible to water damageNot very reliable, prone to stop working over timeQuite high cost per GBCD (Optical Drive)Low Capacity 700MBVery Slow Read / Write speedquite portable, cheap to mail, will work in many devices (PCs, Music Players, Car stereos)Easy to scratch and data loss easyNot very reliable, prone to stop working over timeVery Low cost per unit(10p)DVDLow Capacity 4.7GBQuite Slow Read / Write Speedquite portable, cheap to mailEasy to scratch and data loss easyNot very reliable, prone to stop working over timeVery Low cost per unit (10p)Blu-rayMedium Capacity 50GB+Medium Read write speedquite portable, cheap to mailEasy to scratch and data loss easyNot very reliable, prone to stop working over timeVery Low cost per unitl (10p)Magnetic Tape DriveMassive CapacityVery Slow Read / Write speed. Sequential read / write onlyquite portable, cheap to mailGenerally long lastingMedium reliability over timeVery, very low cost per TBCloud StorageEffectively infinite storageDepends on internet speed, but quite slowCan access anywhere there is access to internetVery durable, due to backups and offsite storage.As reliable as internet connection.Cheap per GB, but may require monthly subscriptionResourcesWhat is difference between magnetic and optical storage device?A magnetic disk is a storage device that uses a magnetization process to read, write, rewrite and access data. The Magnetic disk is made of a set of circular platters. ... Difference Between Magnetic Disk and Optical Disk:. Why are optical storage media considered better than magnetic storage media?Optical storage provides greater memory capacity than magnetic storage because laser beams can be controlled and focused much more precisely than can tiny magnetic heads, thereby enabling the condensation of data into a much smaller space. Which one is the magnetic and optical memory?Optical Storage Devices: Optical storage devices are flat, round disks which spins around its center. The difference with magnetic storage devices is that in optical storage devices LASER light is used to read and write data in disks. Examples are CD, DVD etc. What is magnetic and optical memory?The magnetic and optical disks are the storage devices that provide a way to store data for a long duration. Both are categorized under the category of secondary storage devices. Magnetic disk: A magnetic disk is a storage device that uses a magnetization process to read, write, rewrite and access data.
Is a CDSecondary storage devices are generally separated into three types: magnetic storage devices, such as hard disk drives and tapes. optical storage devices, such as CDs, DVDs and Blu-ray discs.
Is ROM An optical memory?CD-ROM, abbreviation of compact disc read-only memory, type of computer memory in the form of a compact disc that is read by optical means. A CD-ROM drive uses a low-power laser beam to read digitized (binary) data that has been encoded in the form of tiny pits on an optical disk.
Is optical or magnetic faster?they are slow and have limits as to the number of times they can write. ( yes, so do SSDs but those have many times higher MTBF ranges) Therefore, if you're just talking about reading, magnetic storage is much faster than optical.
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