3: Storage Flashcards
the part of a storage system where data is stored (ex. DVD)
storage medium
a piece of hardware into which a storage medium is inserted to be read from or written to (ex. DVD drive)
storage device
AKA direct access - data can be retrieved directly from any location on the storage medium, in any order
random access
data can only be retrieved in the order in which it is physically stored on the medium
sequential access
anything stored on a storage medium, such as a program, a document, or an image
file
name given to a file by the user - used to retrieve the file at a later time
filename
named place on a storage medium into which the user can place files in order to keep the files stored on that medium organized
folder
the primary storage system for most computers - used to store most programs and data used with a computer
hard drive
hard drive that uses flash memory technology instead of magnetic technology to store data - allows for faster operation, reduced power consumption
solid-state drive (SSD)
a hard drive consisting of one or more metal magnetic disks permanently sealed, along with an access mechanism and read/write heads, inside its drive
magnetic hard drive
a concentric path on a disk where data is recorded
track
a small piece of a track on a disk
sector
one or more sectors - the smallest addressable area of a disk
cluster
the collection of tracks located in the same location on a set of hard disk surfaces
cylinder
permanent damage to a magnetic hard drive as a result of the read/write heads touching the hard disk surface (if computer is bumped, if a foreign object gets onto disk’s surface, etc.)
head crash
step 1 in reading/writing data on disk: moving the read/write heads to the cylinder that contains (or will contain) the desired data
seek time
step 2 in reading/writing data on disk: rotating the hard disks into the proper position so that the read/write heads are located over the part of the cylinder to be used
rotational delay
step 3 in reading/writing data on disk: moving the data, such as reading the data from the hard disk and transferring it to memory, or transferring the data from memory and storing it on the hard disk
data movement time
the time it takes to locate and read data from (or position and write data to) a storage medium
disk access time
memory used in conjunction with a magnetic hard drive to improve system performance
disk cache
a hard drive that contains a large amount of both flash memory and magnetic hard disks
hybrid hard drive
dividing the physical capacity of a single hard drive logically into separate areas
partitioning
a type of storage medium read from and written to using a laser beam
optical disc
a low capacity (typically 700 MB) optical disc that is often used to deliver music and software, as well as to store user data
CD disc
a medium capacity (typically 4.7 GB or 8.5 GB) optical disc that is often used to deliver software and movies, as well as to store user data
DVD disc
a high-capacity (typically 25 GB or 50 GB) disc that is often used to deliver high-definition movies, as well as to store user data
Blu-ray Disc (BD)
a drive used with optical discs, such as CD or DVD discs
optical drive
CDs/DVDs/BDs that can be read from, but not written to, by the user (commercially released movies, games, etc.)
CD-ROM / DVD-ROM / BD-ROM
CDs/DVDs/BDs that are recordable
CD-R / DVD-R / BD-R
CDs/DVDs/BDs that are rewritable
CD-RW / DVD-RW / BD-RE
nonvolatile memory chips that can be used for storage by the computer or user - can be built into a computer or a storage medium
flash memory
flash memory chips inserted into products, such as consumer devices
embedded flash memory
a small, rectangular flash memory medium, such as a CompactFlash (CF) or Secure Digital (SD) card - often used with digital cameras and other portable devices
flash memory card
a small storage device that plugs into a USB port and contains flash memory media
USB flash drive
refers to using a storage device that is accessed through a local network
network storage
a high-performance storage device individually connected to a network to provide storage for computers on that network
network attached storage (NAS)
a network of hard drives or other storage devices that provide storage for a network of computers
storage area network (SAN)
AKA online storage - refers to using a storage device that is accessed via the Internet
cloud storage
a credit card-sized piece of plastic containing a chip and other circuitry that can store data - often used for ID cards
smart card
an emerging type of storage technology that uses multiple blue laser beams to store data in three dimensions
holographic storage
the ability of a storage system to recover from an unexpected hardware or software failure, such as a system crash
fault tolerance
a storage method that uses several hard drives working together, typically to increase performance and/or fault tolerance
RAID (redundant arrays of independent disks)
storage media consisting of plastic tape with a magnetizable surface that stores data as a series of magnetic spots - typically comes as a cartridge
magnetic tape
