What’s The Difference Between CDs and DVDs

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Do you know the Differences Between CDs And DVDs

CDs and DVDs possess the same shape and size but that is where the similarities end. The differences lie in the make up of the surface of the disc which are invisible to the naked eye.  There are many different things between the two, such as what they hold and how much they can hold.

When you discover how the data storage is implemented on both CDs and DVDs you will understand how the big difference in capacities is achieved.  As the disc spins a laser is moved across the surface to burn pits in a spiral groove around the disc. Lasers have a wave length and the longer the wave length the bigger the pit. DVD lasers have a substantially smaller wave length than a CD laser. More pits in the same amount of surface area results in a larger amount of information and explains why a DVD is capable of holding so much more data than a CD.

DVDs and CDs are digital storage mediums which basically means that all data is stored as ones and zeros. The pits and lands (where there are no pits) on the DVDs and CDs represent ones and zeros. When the disc is read the laser moves around the discs surface and is reflected off the lands but not off the pits. Microprocessors in the disc drive take the information from the laser and convert it into a digital format that your computer can easily understand.

Because the spiral groove is narrower on a DVD than a CD it is subsequently longer and able to hold more data.  The average DVD can hold 4.5GB of data which is 6 times more than a CD at around 700MB.

Because a DVD has smaller pits and a laser needs to focus on them the physical make up of a DVD is different to a CD.  The DVD has a thinner plastic substrate than a CD making it easier for the laser to pass through and get reflected back.

DVD technology also has a much faster rate of reading and processing data.  The difference in speed is huge with a 52X CD drive reading data at 8Mb a second and a DVD 24X drive reading data at 32MB second.

With Blu-Ray being the new kid on the block and because it has such a massive storage ability DVDs will slowly be phased out as will CDs. CDs will be available for a while yet but as Blu-Ray prices come down and storage needs continually spiral upwards I can’t see them lasting forever. For additional information on CDs and DVDs in relation to presentation and marketing check out the following website CD and DVD Packaging.

Also check out Portable Hard Drive Reviews and Cheapest Portable Hard Drives

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