unit 3 - storage

made this the night before my test

which is typically has a slower access speed backing or internal memory?

backing storage

which has bigger storage backing or internal memory?

backing storage

magnetic drives disadvantages

has moving parts, slower access time and is affected by magnetic fields

optical disks advantages

portable, durable, low cost

magnetic drives advantages

high capacity, low cost per GB

optical disks disadvantages

limited capacity, susceptible to scratches

solid state media advantages

fast access, no moving parts

solid state media disadvantages

more expensive, limited write cycles

what is magnetic drives used for?

long term storage

what is solid states media used for?

fast data storage for portable devices

characteristics of backing storage

all high capacity except CD

examples of magnetic drives

magnetic drive, fixed magnetic hard drive, portable magnetic hard drive, magnetic tape

examples of optical media

CD, DVD, Blu ray

blu ray

requires specific hardware, has high definition video and high capacity data storage

examples of solid state media

fixed SSD, portable SSD, pen drive

what does portable magnetic hard drive and portable SSD have in common?

they are both used for external storage

what is backing storage used for?

long term storage

what is internal memory storage used for?

temporary storage (RAM/ROM)

how does magnetic backing storage media work?

the surface is magnetised so that it holds bits of data, the device that reads media also read the bits held on the surface area.

fixed hard disks/drives advantages

they have a very large memory capacity, they have very fast data transfer raye and fast access times to data

fixed hard disks/drives disadvantages

it can be easily damaged, they have many moving parts which affect overall reliablity, their read/write operation can be quite noisy when compared to solid state drives

portable hard disk drives advantages

fast data access time and transfer rate, has very large memory capacity, can be used as a methods of transferring information between computers

portable hard disk drives disadvantages

can be easily damaged if user accidently drops it or doesnt correctly shut down the drive after use, the data transfer rate is not as fast as for fixed hard drives

CD-ROM/DVD ROM (read only memory) advantages

less expensive than hard disk drive systems, they are portable as they are small and light, data stored on them is read only, so it cannot be accidently overwritten

CD ROM/DVD ROM (read only memory) disadvantages

holds less data than hard disk drives or memory sticks, very sow data transfer and access times as compared to hard disk drives, you cannot add your files to the disks because they are read only

CD R/DVD R (write once only) advantages

cheaper than RW disks, once burned they behave like a ROM

CD R/DVD R (write once only) disadvantages

can only be recorded once so its hard to fix errors, not all CD/DVD players can read them

CD RW/DVD RW advantages

can be written over many times, can use different file formats each ti,e it is used, not as wasteful as the R format because the files/data can be added later

CD RW/DVD RW disadvantages

it can be expensive, possible to accidently overwrite data

blu ray advantages

large storage capacity, fast data transfer rate, the data access speed is also greater then with other optical media, blue ray disks automatically come with a secure encryption system

blu ray disadvantages

expensive disks, encryption problems when used to store videos which may cause the disk to not play, requires specific hardware

DVD RAM advantages

they have long life, possible to rewrite operation over 100,000 times, ability to read data while they are being written, large capacity

DVD RAM disadvantages

not as compatible as R or RW format so many systems wont recognise the DVD RAM format, more expensive than DVD RW, there are better technology

memory stick/pen drives advantages

compact and portable, robust, doesnt need additional software to work on most computers, they are not affected by magnetic fields

memory stick/pen drive disadvantages

cant write protect the data/files, easy to lose, incorrect removal will corrupt the data

flash memory cards advantages

very compact and can be easily removed and used in another device, robust

flash memory cards disadvantages

expensive per gigiabyte if memory when compared to hard disk drives, have a finite life regarding the number of times they can be read or written to, has lower storage capacity than hard disks