What is Storage n n Holds data instructions

What is Storage? n n Holds data, instructions, and information needed for future use. Storage Medium- is a physical item which a computer stores information, data, and instructions. ( also called secondary storage) Ex: Floppy disks, Zip disks, CD’s and DVD’s, tape, and PC cards. Storage requirements for the different users will vary greatly

Capacity of storage media n Capacity- is the amount of information or the number of bytes a storage medium can hold Storage Term Estimated Number of bytes Kilobyte (KB) 1 thousand Megabyte (MB) 1 million Gigabyte (GB) 1 billion Terabyte (TB) 1 trillion Petabyte (PB) 1 quadrillion Zettabyte (ZB) 1 sextillion Yottabyte (YB) 1 septillion

Terminology n Storage device- the computer hardware that records and retrieves items to and from storage media n Writing- the process of transferring data, instructions, and information from memory to a storage medium n Reading- the process of transferring items from a storage medium into memory n Access time- (1) amount of time it takes a storage device to locate an item on a storage medium or (2) the time required to deliver an item from memory to the processor n Transfer rate- is the speed with witch data, instructions, and information transfer to and from a device

Floppy disk n n n -also called the diskette -portable, inexpensive storage medium that is thin flexible -also has a magnetic coating enclosed in square shape plastic shell

Floppy disk continued n An average floppy disk can store up to 500 double spaced pages of text . They can also store photographs, or small audio files

Floppy disk drives n n - is a device that reads from and writes on a floppy disk. External floppy drive- the drive is a separate device with a cable that plugs into your PC

Key Terms Density- is the number of bytes in an area on a storage medium n Downward compatible- they can recognize and use earlier media n Shutter- the metal piece on the floppy disk - The average time for a floppy disk to locate an item is 1/12 of a second n

Characteristics of a Floppy Disk n Floppy disk is a type of magnetic media that allows people to read and write on a disk over and over. n Magnetic Media- use magnetic particles to store data, instructions, and information on a disk surface.

Continued. . n n n Track- a narrow recording band that forms a full circle on the surface of the disk Sector- is the pie shaped figure 80 tracks, 18 sectors

High-Density Floppy Disk Capacity 1. 44 mb Slides 2 Tracks 80 Sectors per Track 18 Bytes per sector 512 Sectors per disk 2880

CDs and DVDs n n Are types of optical storage media that consists of a flat, round, portable disc made of metal plastic and lacquer. Store software, data, digital photographs, movies, and music

Characteristics of CDs and DVDs Are not magnetic media, instead they are optical media that store items such as data and instructions n Uses microscopic pits (indentations) and flat areas that are in the middle layer of the disc n

How a CDs and DVDs are read n n n A high powered laser light creates the pits. A lower powered laser lights reads items from the disc by deflecting light through the bottom of the disc, which is usually gold or silver The reflected light is converted into a series of bits the computer can process A land causes the light to reflect, which is read as binary digit 1. Pits absorb the light; this absence of light is read as binary digit 0. Items are commonly store items in a single track that spirals form the center to the outside edges of the disc

Care of CDs and DVDs n n n Never bend a disc; it may break If a disc becomes warped or if its surface is scratched, the data on the disc may be unreadable Exposing to extreme temperatures or humidity could cause them to warp. The ideal temperature is 50 -70 degrees Stacking discs, touching the undersides or exposing them to any type of contaminant may scratch it Best place to store the CD or DVD is in the

CD-ROMs n n n Is used for storing data, instructions and information in addition to audio and video Can only read the content on the discs, meaning that they cant be erased A typical CD-ROM can hold from 650 MB to 1 GB of data

Picture CDs and Photo CDs n n n Is a small data CD that stores up to one role of film using a jpg file format Picture CD usually is 1024 x 1536 pixels The cost of a picture CD is about 10 dollars per role of film n n Stores multiple rolls of film using the Image Pac or PCD Designed for commercial and professional users Resolutions ranging from 128 x 192 to 4096 x 6144 pixels Store images from 35 mm film, negatives, slides and scanned

CD-Rs and CD-RWs n n n Multi session CD which user put there own information on to To be able to write on the CD-R you need a CD-R drive to burn the CD Has a speed of 40 x or more n n CD-RW is a rewritable CD that can be erased. Is much like a floppy disc Only down fall is that the more it is erased the more faulty the CD becomes The CD-RW drive has a speed of 52 x or more

DVD-ROMs n n n DVD stands for digital versatile disc or digital video disc Can store up from 4. 7 GB to 17 GB the storing capacity has more than enough to hold a telephone book containing every resident in the United States The goal of the DVD technology is to meet the needs for home entertainment, computer usage and business data DVD-ROM players can read up to speeds 48 x or more Look just like the CD-ROM and sometimes are easily n n n First involves making the disc denser by packing the pits closer together Second involves using two layers of pits. For this to work the lower layer of pits is semitransparent so the laser can be read through the upper level. This technique doubles the storage capacity of the disc Finally some discs are double sided and need to turn it over when you are done with the one side

DVD-ROM Storage Capacities Sides Layers Storage Capacities 1 1 4. 7 GB 1 2 8. 5 GB 2 1 9. 4 GB 2 2 17 GB

TAPE Tape is a magnetically coated ribbon of plastic capable of storing large amounts of data and information at a low cost. q Tape is no longer used for storage purposes; instead, most home users and businesses use tape for long-term storage and background. q

TAPE DRIVE n n n q q Comparable to a tape recorder. Today’s computers use tape cartridges. Tape cartridges are small, rectangular, plastic housings for tape. They are slightly larger than an audio-cassette tape. On larger computers, tape cartridges are mounted on a separate cabinet called a tape library. Reads and writes data and information on a tape. Transfer rate of tape drives range from 500 KBps to 1 MBps. To access a certain piece of data, you must forward or rewind the tape.

PC CARDS n n n A thin, credit-card-sized device that fits into a PC Card slot Add storage, additional memory, fax/modem, networking, sound, and other capabilities Commonly used in notebook computers They are available in three different sizes according to thickness- Types I, III. Cards that house a hard disk have storage capacities of up to 5 GB

MINI MOBILE STORAGE MEDIA n n n PDAs, digital cameras, music players, and smart phones are devices that provide the user with instant access to technology Because they have limited internal storage, they require these mini mobile storage devices to store digital images, music, or documents Most are no larger than a postage stamp

Compact. Flash n Storage capacity is 16 MB to 1 GB – Flash memory card – Used for digital camera, PDAs, notebook computers, printers, music players, cell phones

Secure Digital n n n 16 MB to 256 MB Flash memory card Used for digital cameras, PDAs, cell phones, digital video cameras, car navigation systems, e-books

Memory Stick n n n 16 MB to 128 MB Flash memory card Used for digital cameras, notebook computers, photo printers

Microdrive n n n 1 GB Magnetic media Digital cameras, PDAs, music players, notebook computers, video cameras

USBDrive n n n 32 MB to 2 GB Flash memory card Plugs into any USB port to function as a mini hard disk

SMART CARD Similar in size to a credit card or ATM card n Stores data on a thin microprocessor embedded in the card n Contain processor and have input, output, and storage capabilities n

MICROFILM AND MICROFICHE n n n Store microscopic images of documents on roll or sheet film Microfilm is a 100 - 215 foot roll of film Microfiche is a small sheet of film, usually about 4 inches by 6 inches A computer output microfilm is the device that records the images on the film Libraries use these to store back issues of newspapers, magazines, and genealogy records