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STORAGE DEVICESDone by: Mohammad Fadhullah bin Matyassin.

: Mohammad Daud Bin Mohd Zain.

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OBJECTIVESDefine what is Storage Devices.List down classification Storage devices.Define Primary Storage (RAM & ROM).Define Secondary Storage/ Backing Storage.Name at least 3 storage devices of parts of computer.

State ONE function of at least THREE storage devices of parts of computer.

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IN REAL LIFEWhat is these thing really do in our daily life?

What kind of work or job that associated with these devices?

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APPLICATION• A computer repair technician is a person

who repairs and maintains computers.

• The technician's responsibilities may include

• building or configuring new hardware,

• installing and updating software packages,

• and creating and maintaining computer networks

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WHAT WE KNOW IN GENERALSpeed up computer process.Improve loading time.Always associate hard disk with RAM. And thinks its the same. IT’S A MYTH!

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DEFINITION STORAGE DEVICESStorage devices are devices that can store data or information.

There are various type of storage devices. Different devices are suitable for different tasks.

Data can be stored either in the ‘Internal Memory’ or on a ‘Storage Devices’.

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CLASSIFICATION OF STORAGE DEVICEPrimaryThis storage is the fastest memory in your computer

Is used to store data while it's being used.

For example, when you open a program data is moved from the secondary storage into the primary storage.

Secondary Is a storage medium that holds information until it is deleted or overwritten regardless if the computer has power.

A floppy disk and hard disk are both good examples of secondary storage devices

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THING ASSOCIATED WITH STORAGE DEVICESize/ CapacitySpeed

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WHAT IS RAM AND ROM?RAM ROM

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RANDOM ACCESS MEMORYTemporary, short-term working memory.Only works when the computer is turned onIt is also known as “Volatile Memory” because data disappears if the power is switched off.

Each time you start a program e.g. MS Word, it is loaded into RAM.

The amount of RAM influences processing power, speed and how many programs can run at the same time.

Many computers are now sold with 4 to 8 GB of RAM.

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READ ONLY MEMORY It is permanent, long-term memory which cannot be erased or changed in any way

It is also known as “Non-Volatile Memory” because it doesn’t disappear after the computer is switched off.

ROM chips instruct the computer how to load the operating system from the hard drive into the computer’s memory.

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HARD DISKHard Disks are the main internal backing store usually found inside computers.

It is a non-volatile storage device. Data is stored on a spinning disk with a magnetic surface known as magnetic media.

It can store a large amount of data.There is also an external hard disk which connected to the computer system by a USB cable or other means.

It provides additional storage space for the computer system

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ADVANTAGE AND LIMITATION OF HARD DISK

Advantages LimitationsNecessary to support the way your

computer worksFar slower to access data than ROM

or RAM chips

Large storage capacity Can crash which stop the computer from working

Stores and retrieves data much faster than floppy disk or CD/DVD

Regular crashes can damage the surface of the disk, leading to loss

of data in that sector

Stored items are not lost when you switch off the computer

The disk is fixed inside the computer and cannot easily be

transferred to another computer

Cheap on a cost per megabyte compared to other storage devices

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ZIP DISKVery popular as a backup medium before CD-RWs were developed and became cheap enough for everyone to use.

Look similar to a floppy disk but are a little bit thicker.

They can store around 100Mb of data – 70 times more than floppy disk.

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ADVANTAGES AND LIMITATION OF ZIP DRIVE

Advantages Limitations

Stores more data than a floppy disk

Almost obsolete now

Compresses data, reducing the file size, so more data can be stored

Need a separate zip drive to read the disk

Portable More expensive than floppy disks.

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FLOPPY DISC One of the oldest types of portable storage devices

still in use. Have been around since the 1980s. Store up to 1.44 Mb of data which equivalent to

around 300 pages of A4 text. Graphics and WordArt cannot be stored because

there have larger size than the size of floppy disk.

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ADVANTAGES AND LIMITATION OF FLOPPY DISK

Advantages Limitations

Portable – small and lightweight Not very strong – easy to damage

Inexpensive Data can be erased if the disk comes into contact with a magnetic

field

Useful for transferring small files between home and school

Quite slow to access and retrieve data when compared to a hard disk

Security tab to stop data from being written over

Can transport viruses from one machine to another

Can be used many times Small storage capacity

Many new computers do not have floppy disk drives

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CD-ROM Also known as Optical Storage Devices. Data is burned onto the surface of the disk using

a laser beam in the CD drive. A Laser beam is also used to read the data stored

on the disk. A typical CD can store around 650 Mb of data –

equivalent to 450 Floppy disks.

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ADVANTAGES AND LIMITATION OF CD ROM

Advantages Limitation

Small and portable Fairly fragile, easy to snap or scratch

Very cheap to produce Smaller storage capacity than hard drive or DVD

Most computers can read CDs. If there is no CD drive, a DVD drive

can usually read them

Slower to access than the hard disk

Fairly fast to access the data – quicker than a floppy disk or

magnetic tape

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DVD-ROMShort for Digital Versatile Disc or Digital Video Disc, a DVD or DVD-ROM.

is a disc capable of storing large amounts of data on one disc .

today they are widely used for storing and viewing movies and other data.

To play a DVD on a computer a user must have a DVD drive as well as a DVD player,

One of the most common DVD's is the single-sided, single-layer disc, capable of holding 4.7 GB.

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ADVANTAGES AND LIMITATION OF DVD ROM

Advantages Limitations

Very large storage capacity DVDs do not work in CD drives

Sound and picture quality is excellent, making them ideal for

storing films with video and sound

There is no single standard of DVD

DVDs are now mass produced so they are relatively cheap

They can be easily damaged by breaking or scratching

DVD players can read CDs

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PENDRIVE

Alternatively referred to as a USB flash drive, data stick, pen drive, keychain drive and thumb drive, a jump drive, portable drive.

Typically small, lightweight, removable and rewritable. They consist of a small printed circuit board which is

encased in a plastic or metal casing. They usually have a removable cap which covers and

protects the part of the stick which is inserted into a USB port.

Are available from 1 Gb up to 6 Gb.

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ADVANTAGES AND LIMITATION OF PENDRIVE

Advantages Disadvantages

More compact and portable than floppy disks or CDs/DVDs

At the moment, the cost per megabyte of storage is more expensive than floppy disks,

CDs or DVDs

Hold more data than floppy disk and nowadays often more than a CD

They can be easily lost

More reliable than a floppy disk because they have not moving parts

The metal part which is inserted into the USB port can be snapped off if they are handled

roughly

They are being developed with fashionable looking outer casings and are almost

becoming a ‘fashion accessory’ much in way of a mobile phone.

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MEMORY CARDAlternatively referred to as a flash memory card

type of storage media that is most commonly used in digital cameras, digital camcorders, handheld computers, MP3 players, PDAs, cell phones, game consoles, and printers, to store pictures, videos, music, and other data.

There are a handful of different types of memory cards on the market, each varying in size, compatibility, and storage capacity.

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ADVANTAGES AND LIMITATION OF MEMORY CARD

ADVANTAGES LIMITATION

CAN HOLD LARGE AMOUNT OF DATA 4 TO 16gb

SOMETIME EASY TO LOOSE DUE TO ITS SIZE WHICH IS

VERY SMALL

VERY PORTABLE SOME OF THE CARD ARE NOT COMPATIBLE WITH LAPTOP OR COMPUTER

COST EFFECTIVE IN TERMS OF PRICE

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EXTERNAL HARD DISC

External drives are often stored in an enclosure that helps protect the drive and allow it to interface with the computer, usually over USB or eSATA.

External hard drives come in many shapes and sizes. Some are large, about the size of a book, while others are about the size of a cell phone.

External hard drives can be very useful for backing up important data and taking with you on the go. They can store a lot of information, including music and pictures.

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ADVANTAGES AND LIMITATION OF EXTERNAL HARD DISK

ADVANTAGES LIMITATION

External drives are easier to transport from computer to

computer than internal

generally cost much more for the same amount of

storage space than internal

externals are better for storing data that you'd like to share with people easily

transfer/access files more slowly than an internal drive. (Copying things to and from an external take longer than

your regular hard drive)

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HOW TO USESTORAGE

MEDIA

FLOPPY DISK FLOPPY DISK DRIVE

CD and DVD DVD - CD ROM DRIVE

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HOW TO USESTORAGE

MEDIA

PENDRIVE AND

EXTERNAL HARD DRIVE

USB DRIVE