How many times can a CD be burned? Currently, CD-RW discs can be rewritten approximately times. What can I play a CD-R on? How do I know if my CD is rewritable? How do I wipe a disk clean Windows 10? How can I format a write protected CD?
Insert the write-protected CD into the drive. Can you cut CDs with scissors? Can you paint a CD and it still work?
Does microwaving a CD destroy it? Can a broken CD be read? Do CD players still exist? Or is there a more technical reason, ie. CDs store their data magnetically correct? Sorry if that's completely wrong; I have no idea how CDs work. Data on a regular CD is stored by making pits holes , or not-holes lands , on the CD medium. The pits disturb the reflection of light. Transition from a 0 to a 1 or vice versa is determined by the start or end of a pit this is called NRZI encoding.
There is further complication as these bits are the "channel code", not the content bits; the latter are recovered by decoding the former. And then some of the "content" bits are really Error Correction Code bits. But ultimately, the bits are encoded via holes or not-holes in a reflective layer of metal, usually aluminum.
A CD-R works somewhat the same. It has a reflective surface, but this surface is covered by a dye. Light is either reflected or not. Note: Rewriting with the same image or a image with only the right bit changed would seem to be technically possible, but there are limits as to what could be done.
The best you could do would be to burn a "pit" in the middle of a long "land". Since lands have a maximum length of ten bit-times, and both pits and lands have a minimum length of three, this would only be possible where an existing land was nine or ten bits long, and the only possibility would be a pit three or four bits long. Doing this would add two bit flips, and this in turn would necessitate changing ECC bits at other places in the same block.
The chances that every such change could be done by adding a pit in the middle of a land are very, very small, even if there was software or drive firmware that would allow the attempt.
The disc comes out of the box reflective, but then your drive burns the solid thin chemical dye layer below the plastic and "roughens" it so it becomes slightly transparent. This makes the light disperse when a laser hits it, thus it counts as a zero essentially since the laser gets little light back. There is no way to fix this burned area and make it reflective again.
The only way to wipe the data, is to turn into Asus makes software called E-Hammer that may work with non-Asus drives:. The CDs you buy in a store are pressed from a mold. CD-Rs are burned with a laser. While they're not physically identical, they work just the same. Yes, both audio and data CDs can be duplicated.
You can even create audio CDs that are compilations of other audio CDs. The first time my father use this feature, i dont really believe that he could write DVD several times. This is really nice feature! However, the reverse has been happened. It was successfully; however, I am afraid to say that I didn't notice any significant benefits.
However, this doesn't matter at all. Because there are three main advantages to using USBs. Secondly, USBs are flexible and easy to move. Finally, USBs are more safety and keeping for data. On the other hand, there are significant problems with use of the CD's. In the first place, using CD's can cause in losing data after a long period of time, for instance, if you have copied data on a CD, and then CD has been scratched. So the data could be lost.
Because there are three main advantages to using USB flash drives. Secondly, They are flexible and easy to move.
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