1. By:Billy Nguyen Teacher: Luce

2. Introduction Within technological terms, storage mainly refers and relates to computer devices that keep or retains information. Data storage is a very significant component of computers, which allow the computer or device to be able to retain any information, over long periods of time. Storage also refers to external memory that would be used for the computer to comprehend and make use of information. Such devices would include anything from magnetic tape, CDs and Universal Serial Buses. Storage is the perfect path to keep needed information and to be able to transfer information quickly and easily from one place to another.

3. Differences! Memory and storage are two distinct components! Differences between memory and storage are: - Storage has a much larger capacity than memory units - Usually deals with retaining memory for long periods of time -Storage devices are commonly CDs, disk drives/hard drives and USBs - Storage devices process slower than memory - Also differs from primary storage/memory because the CPU cannot access the data directly. The computer must use in or out put channels to access secondary memory.

4. Advantages! There are significant advantages of storage over memory: - Storage is preferably used because of its large capacity to retain data - Storage units also keep data for extended periods of time - Secondary data does not lose the saved information or data even if the device is shut-off, this is also referred to as being non-volatile - Since storage devices are non-volatile, this is ideal for backing up information -Storage devices are also much cheaper than memory devices!

5. History! Computer storage has a brief history! Since technology has been advancing so fast in the past decades we have a brief history of computer storage! Here is a time line of the major storage devices that have been of significance SELECTRONTUBESELECTRONTUBE 19461960 MAGNETICDRUMMAGNETICDRUM 1970 PUNCHCARDSPUNCHCARDS 1980 M A G N E T I C TA P E HARDDRIVESHARDDRIVES 1990 F L O P Y D I S K S L A S E R D I S K S U S B F L A S H D R I V E

6. The Selectron tube - First invented by Jan A. Rajchman in 1946 - very early form of storing data/ computer memory - capacity of 4096 bits! - 10 by 3 inches in dimensions - at the time the selectron tube was too expensive - also had issues producing this devices - never really became a success to public

7. Magnetic Drum Invented by Gustav Tauschek Used for computer memory mainly in the 1960's The drum was metal cylinder that is surrounded with a magnetic recording material The magnetic drum had a capacity of approximately 10 KB The drum worked because it was surrounded by tapes which had information that could be read using a track which enabled the information to be processed when the drum rotates At the time, the magnetic drum was fairly useful for it was less expensive for a device that was fast and could hold reasonable amounts of data

8. Punch Cards - Originally punch cards were made and used before computers in 1725 - Punch cards were frequently used for computer memory in 1975, made and produced by mainly IBM - Punch cards operated by punching holes in specific areas of the card that would represent data because of the combination of punched holes - Punch cards for computers had to be set in a binary format so the computer could comprehend the given combinations of a punch card - Punch cards were also used as legal documents because they stored information that could be read by computers and not be comprehended or read normally

9. Floppy Disk! - First invented by IBM in the early 1970’s, by David Noble - A small plastic covered case with a metal slide used to store - information and data - Information will be read when entered into the correct disk drive which then accesses information in the silicon disk inside the floppy disk - The floppy disk allowed information to be easily transferred from one computer to another - A floppy disk in the mid 1970 could usually store up to 90kb - As the need for floppy disks grew, eventually in the 1990’s they reached capacities of 20MB – 200MB - Floppy disks were soon replaced by compact disks so this type of storage use decreased

10. Magnetic Tape - Magnetic tape was originally invented in 1928, to record music - It was not until 1951 when magnetic tape was reinvented to retain data - In the 1980's magnetic tape was then commonly used to store data on the PC, and cassettes - The tapes were commonly used in the 1970's and 1980's for maintaining data - Magnetic tape was also portable and less expensive but they tended to be too slow and could not retain as much data - Magnetic tape seems to be outdated, but surprisingly they are still in use today to back up data on networked computers

11. Laser disks From the old days to the new! - Laser discs were first introduced in 1978 - The first laser discs were 12 inchs in diameter and could play video and audio for approxiamtely 60 minutes - Compact discs (CD) were much more effiecient and smaller in size - Compact discs were capable of storing much more digital information and had varied in types such as the CD – ROM (compact disc read only) - After CDs came DVDs (digital versatile discs) which were capable of accessing information much faster and was able to play video and audio formats at larger capacities in the range of 4 -17GB, Blue ray was an advanced high definition of DVDs which could hold up to 27GB and could transfer data at 36Mbps

12. Hard drives - The very first hard drive or hard disk was invented by IBM in 1954 - It was not until the late 1980's that globally people needed a device that would be more efficient and reliable - Hard drives vary in capacity from 120GB – 2TB, the size of a common hard drive for a desktop is about 3.5 inches but there have also been 2.5 – 0.8 inches for laptops and mobile devices - Hard disks operate by accessing stored information through the magnetic disk which spins at very high speeds revolving around an axle that commands read and write operations that store or use the information - The advantages to a hard drive is it can access information is lesser than a second, it stores large amounts of data, is non-volatile and the device is fairly compact for the operations it provides for the computer

13. USB Drives - USBs were created in 1996 - The acronym for USB is Universal Serial Bus - This type of secondary storage by far the most effective storage device known to the public - The USB is much more compact in size, can store astounding amounts of data, and is compatible to all computers - The USB is an external drive that allows users to transfer data from one computer to another - The USB operates simply once it is plugged into a USB port on the computer where the user may move files quickly and easily in and out of the device - capacities of a USB commonly refer to the size of the USB and sizes can vary from the size of a thumb to being the size of a mobile cell phone - Capacities have varied from being 8MB in 2000 to 256GB in 2010

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17. Bibliography http://royal.pingdom.com/2008/04/08/the-history-of-computer-data-storage-in-pictures/ http://gadgets.fosfor.se/history-of-data-storage/ http://en.wikipedia.org/wiki/Computer_data_storage Smyth G., Stephenson C.(2002).Networks, Interfaces and Integrated Circuits. Toronto: Holt Software Associates. http://en.wikipedia.org/wiki/Universal_Serial_Bus http://en.wikipedia.org/wiki/Hard_disk_drive http://computer.howstuffworks.com/hard-disk.htm http://en.wikipedia.org/wiki/Floppy_disk