Even more complex is the mode of preserving data for backup and archival purposes. For backing up and saving any data, what is requisite is a hardy backup media. Any authentic backup media should qualify certain criteria. First and foremost, it should be easily available at an economical price, so as to enable the user to store data in bulk, at a low price. A good backup media should be reasonably fast and should offer an optimum speed. Finally, any worthwhile backup media should be reliable and almost flawless. Over the years, various storage media entered the market, with their own unique set of features and abilities. The list of options was further widened with the entry of CD-R into the market, in 1979.
The very first CD was invented by Sony and Philips and was initially used for transferring small amounts of data. In the beginning, it failed to pick up as a back up device, owing to its high cost. However, with a substantial fall in the prices in the following years, it soon replaced the floppies, which are almost extinct now. The storage capacity of CDs was further enhanced with the advent of DVDs, after 1995. DVDs work the same way as CDs, but, have a much higher storage capacity. CDs and DVDs offer a good level of reliability and have a life span ranging from 10 to 100 years. They are easy to use and furnish a medium speed. CDs and DVDs are very popular and easily available at low prices. Hence they prove to be reasonably suitable as backup media. However, they are in the risk of becoming obsolete, in the next few years, with the arrival of next generation media such as thumb drives and compact flash disks, which use static, non-mobile RAM for saving data. Despite this factor, CDs and DVDs are extensively being used as back up media and thus it is vital to have the knowledge regarding how to protect CDs and DVDs from data loss.
CDs and DVDs demand a careful handling. A few important steps and precautions that should be taken, so as to preserve CDs and DVDs are as follows:
Handling and Care
Minor scratches on the surface of a CD or a DVD cause no harm, as the laser penetrates below the surface to decipher data. However scratches which are deep and run along the track are lethal and may do considerable harm to the quality of backed up data. Hence the optical disks should always be handled delicately by the edges only. In case of CDs, the data containing layer is located directly below the label side. Any deep scratch on the label side may lead to loss of data. Thus never use any stick-on labels on this side. The adhesive may harm the surface. Do not use sharp tipped pens or pencils to write on the label side. Only felt tipped pens should be used to label a CD or DVD. Always write on the clear inner hub lying at the center of any optical disk.
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