CDs, DVDs and Blu-ray Discs
CDs can be used to store relatively small amounts of data very easily. They are cheap, easy to access and popular for storing music, but are fairly fragile and unreliable. With a top recording speed of 52x and a capacity of 700MB, users can create their own albums to be played in stereos in a matter of minutes, or back up relatively small computer files like word processing documents and spreadsheets.
CD-R discs are suitable for permanently recording data, whereas CD-RW discs can be overwritten with fresh data multiple times.
DVD discs can store around seven times the amount of data that a CD can, albeit at a slightly higher price. Ideal for storing and sending large files such as complex animations or videos to friends, colleagues or prospective clients through the post, the speed at which DVD discs can be written varies from product to product. Like CDs, data can be written to DVD-R discs just once, but content on DVD-RW discs can be altered on multiple occasions.
Blu-ray discs are designed to succeed DVDs and can hold approximately six-times more data (thats the same as 42 CDs). Blu-ray discs are most commonly used for high definition movies and programmes. The discs are more expensive to buy and Blu-ray players and writers are still relatively uncommon, so make sure your computer has the right hardware.








