Uploaded byYohniki Gordon
Optical Storage
Optical storage uses light to read data stored on optical discs or memory cards. Common optical storage devices include CDs, DVDs, Blu-Ray discs, HD DVDs, USB flash drives, memory cards, and smart cards. CDs hold around 800MB of read-only data, while DVDs and Blu-Ray discs can hold significantly more data up to 50GB in writable formats, using laser light of different wavelengths to read small pits in the disc's surface. Flash memory cards and drives store data electronically in non-volatile memory.
More Related Content
Similar to Optical Storage
Optical Storage
- 1.
- 2. WHAT IS OPTICALSTORAGE •Optical storage is data that is stored on optical readable medium. Light is used to aid the device in reading the data that stored. Optical storage devices range from CD-ROMs which was established in 1982 to Flash drives which were introduced in 1999. The latest optical storage to date is the Blu Ray Disc.
- 3. READ-ONLY OPTICAL DISCS •Compact Disc – CDs have Read-Only Memory that can hold around 800MB of data. The data cannot be edited or deleted once its added to the disc so therefore it cannot be deleted ‘accidentally’. CDs are non-volatile.
- 4. •Digital Versatile Disc (DVD)– DVDs gave Random-Access Memory. They can hold up to a total of 4.7GB of data. There are also dual-layer DVDs that can hold up to twice that amount.
- 5. • Blu-Ray -Blu-Ray discs are a recent replacement of DVDs. These disc can hold from 25 – 50GB of data. A dual-layer can hold up 100GB. Blu-Ray disc are consider random-access devices. The ‘Blu’ in Blu-ray is of a fact that the light in the laser is blue instead of red. Blue light has a shorter wave-length than red light
- 6. •HD DVD –High-densityDVD (HD- DVD) disc can hold around15GB of data (a dual-layer HD-DVD can hold twice that)HD-DVDs are random- accessdevices. HD-DVD can be used in the same ways asDVD-ROM but, since they can holdmore data, they are used to store very high-quality, high-definition(HD)videos.
- 7. •USB Memory Stick– Memory sticks ( thumb drive), since invented has made many other forms of portable storage become obsolete such as CDs and DVDs. The popular question asked is “why burn a CD or DVD when you can easily copy the files onto a flash drive?” USB memory sticks are
- 8. • Memory card- Many of the devices used today require memory cards to store data such as cameras. Memory cards are compact and non- volatile. One of most common formats of memory card are SD Cards. Some phones also have extra internal memory card to store data so don’t have to depend on memory
- 9. • Smart Card- Many credit cards (e.g. ‘chip-and-pin’ cards), door entry cards, satellite TV cards, etc. have replaced the very limited storage of the magnetic strip (the dark strip on the back of older cards) with flash memory. This is more reliable and has a much larger storage capacity. Cards with flash memory
- 10. WHAT HAVE YOULEARNT? 1)What would you consider the sim card in your phone? 2)What is the max capacity of a Blu-Ray Disc? 3)What is used to read the data off a Optical Disc? 4)What is the meaning of RAM? 5) Are flash drives volatile or non-valatine?
- 11.