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How CDs work?

Optical disc is a medium customarily used for storing various types of video files, music, data and more. optical disc is less developed in terms of quality and capacity. Optical Discs has four types they are CD, DVD, HD-DVD, Blu Ray. In each of these types has a different quality and capacity, but has the same function as the storage medium.

The advantages of storing data / files on the types of CDs because the price is much cheaper and also the data will not be stored exposed to the virus may be damaged or deleted manually because the data store is Read-Only and can only be removed using certain applications such as Nero, Ashampoo Burning studios, and other similar applications.

How does the CD / DVD drive to read the data on optical discs?

A CD / DVD Drive when going to read an optical disc (optical disc) be it CD, DVD, Blue-Ray, and similar by using a laser with a lower intensity and will be directed to the disk surface. When the laser beam to reach a pit that is bouncing back with a lower intensity than when directing the laser on the land. Thus it is better if an optical disc is scratched or exposed to light either sunlight or artificial light is too bright and berlibihan the optical disc that contains data belonging to you will not be able to read properly and may be lost. Here we will try to explain about the difference between CD, DVD, Blue-Ray / HD.

  A. CD (Compact Disk)

Type optical disc CD is a first generation that replaces / shift the existence of diskette (floppy disk) at the time, because the optical disc CD has a data storage capacity larger than a diskette, while in terms of price is not much different. Optical disc CD ordinary and widely used to store movies / small resolution video, music video clips, software / applications and other important data that will be used for various kinds of purposes, since at the time of first use of the Internet is still not widely used because of the price internet service is not affordable for most people / groups.

An optical disc CD has a storage capacity that is equal to 700 MB of data, the optical disc CD Develop a single layer using a red laser technology with a wavelength of 780 nm (nanometers), whereas its own data storage location (layer) on the top of the optical disc CD , so if the top (the label of the brand CD) is damaged or scratched, the CD will not be in use again, as well as the bottom if dirty much covered dirt or scratches so much red laser optics will be difficult to read the data that requires a long process to read , you should first clean with a soft cloth that is not scratched the surface of the CD before use. CD disc itself there are two types of CD-R (CD-Read) that can only be used to read the data, CD-RW (CD-Rewriteable) that CD rewritable data using applications such as Nero and Ashampoo burning.

  B. DVD (Digital Versatile Disc)

DVD is an optical disc second generation of optical disc that has a larger capacity 7 times that of a CD. In each DVD has a total capacity of data storage media of 4.7 GB for single-layer DVDs, this DVD can play various types of video or film types with a screen resolution of 720x480 pixels, and therefore no wonder that today the whole movie there are at present using the media as a medium for play movies, because they were cheaper and also more economical than having to buy 7 disc CD with the capacity to rival the size of the existing storage capacity of a DVD.

DVD is use red laser technology with a wavelength of 635-650 nm (nano meters), while the location of data storage media (layer) is in the middle of a DVD disc, so that the data will be safe from damage to the disk, but you should avoid the bottom from dirty or exposed to light / excessive light. Just as on an optical disc CD if you violate the terms of the optical disc DVD will be difficult to read the data and files that have been burned. DVD discs also have a greater capacity that the size of the data storage of 8 GB, these discs usually consists of a Dual-Layer. Variants of DVD disc is same as CD that composed of DVD-R (DVD-Read) and DVD-RW (DVD-Rewriteable).

  C. Blu-Ray Disc and HD-DVD (High Definition DVD)

Blu-Ray and HD-DVD are two optical storage disc technology that offers a new high definition TV (HDTV high definition television), meaning that the quality of video and film display that can display better than the DVD. In a DVD optical discs can support display resolutions up to 720x480 pixels, but HDTV (High Definition Television) can run videos with resolutions as high as 1920x1080 pixels.

Blu-Ray and HD-DVD itself utilizes laser light purple - blue for reading and writing data on the optical disc. This laser has a smaller wavelength that is 405 nm (nanometers) than a red laser used in DVD and CD discs that can provide a recording density (recording) higher. An optical disc Blu-ray Disc has a storage capacity of 25 GB of data on a single layer, while HD-DVD has a storage capacity of 15 GB single layer of data. The location / area for data storage layer on the Blu-Ray is located on the bottom, while the HD-DVD discs area / data storage layer is located at the center as well as on a DVD.