Does digital information degrade when copied (even minutely) in spite of error checking due to entropic forces
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Copying a digital file, by definition, always gets you an exact duplicate. The media you save it to may degrade, but the digital file will not change via entropy.\n\nHere is the main difference between analog and digital. In digital, the information is stored as a series of numbers. To make sure that the numbers don't change, they are stored with things called "checksums". Basically a mathematical formula that comes up with a number that represents the block of data.\n\nSo let's say for sake of argument, we use a really simple checksum. Add up all the numbers and call that sum our checksum. And say for sake of argument, the data numbers are 200, 200, 200, 200 and 200, so the checksum is 1,000.\n\nThe digital file would have the five "200's" and the number 1,000 as a checksum.\n\nNo when you send the file, the receiving computer gets the five "200's" and the number 1,000. It adds up the 200's, gets the sum of 1,000, and now knows for certain, that the digital data is correct.\n\nNow lets say something does happen, and one of the numbers changes via entropy, sunspots, solar flares, or the fact that its Tuesday, and one of the 200's becomes 199. The receiving computer adds up the numbers and gets 999, so it knows the data is bad. It will ask the originating computer to resend the data. If it fails again, it will declare the file invalid, and you will not get a copy.\n\nThat's the beauty of digital. If the numbers don't add, the copy is invalid. So the supposition that the data in future files will be different is incorrect.\n\nAs I mentioned before, media CAN go bad. So if you put information on a hard disk, tape, CD or DVD, any of these can go bad. But that is a failure of the media, not the digtal transfer.\n\nIf you copy a digital file 1,000 times, 10,000 times, or 100 million times, it will always end up the same.\n\nAdditional information:\n> So what happens when a 200\n> becomes 199 and another becomes\n> 201. You still get 1000.\n\nExcellent question!\n\nI gave a pretty rudamentary example of a checksum. In real life, checksum algorithms, CRC being the most popular (Cyclic redundancy check - See Wikipedia article referenced below). \n\nCRC calculations rotate through all the values during calculation, so it's clear when one byte has changed. Think of it like this. If we take my previous example, but we did it for each digit, like this.\n200 = checksum of 200\n200 + 200 = checksum of 400\n200 + 200 + 200 = checksum of 600\n\nThe end result would be the that any one data byte changing is reflected in the checksum. But the file would get pretty big. Logorithmically!\n\nBut if you add up the check sums, you end up with one number, that verfies the value of every individual byte!\n\nSo let's apply this to your example (but lets make it three digits so this answers isn't huge!)\n200 = 1st checksum is 200\n200 + 200 = second checksum is 400\n200 + 200 + 200 = third checksum is 600\nTotal checksum is 1200.\n\nNow lets apply the error you introduced\n200 = 1st checksum is 200\n200 + 199 = second checksum is 399\n200 + 199 + 201 = third checksum is 600.\nTotal checksum is 1,199!\n\nSo even though the error gets past a simple summary checksum, it doesn't pass a cyclic summary. And it doesn't take up any additional space.\n\nNow the CRC algorithm is actually more complex than this, so it checksums on many levels. The file you start with is perfectly duplicated every time, or it will fail to copy at all.
312435
Oooo, bad noises. If it was a problem with the circuit board I could give a suggestion, but those noises mean that the "heads" that read the data off the platters were hitting something inside the dirve, and from your description of the sounds, I'd say what they were hitting was the platters, where data is stored in a hdd :( Bad news, that. Some of your data would probably still be recoverable, but not at home, not without a clean room. There are companies who specialize in this, but it's expensive, and they usually charge by the megabyte. Google "data recovery specialists" if you want to find one near you.
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Lossy compression techniques:\nhttp://en.wikipedia.org/wiki/Lossy_data_compression#Lossy_compression_methods\n\nLossless compression techniques:\nhttp://en.wikipedia.org/wiki/Lossless_data_compression#Lossless_compression_methods
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Word descrambler linked below.
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no, burning at a slower speed is better for an older drive so it is able to keep up with the information from the computer.  it has nothing to do with the bitrate of the music.\n\nIm going to edit My Answer and say this, You ask about the Quality of the music, and im still going to say no, BUT it does improve the quality of the DISK and the actual DATA.  but as far as sound goes, you wouldn's see any significant difference.
402543
http://www.mcdpri.com/mcdpri/data-destruction-standards.htm
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Direct copies don't degrade, but if you put it on a CD and then rip it again it wil. Recompressing is what does it. If it's an MP3, keep it as one.
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Would it help to encode the characters before storing them, and decode the characters when reading them? That way you can easily mix character sets.\n\nRawlyn.
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http://www.jufsoft.com/badcopy/?rid=BadCopy&vid=3.72&bid=1012
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Good Joke, Programmer must have died of Exhausion ! Ha Ha Ha...This reminds me, an old incidence, while persuing my Post Graduation, to submit my Dessertation thesis I had to work on "Fortran 20" Computer [Now it may be seen in Museums, if any of them ae left !] where we need to feed data in the form of Punch Cards. I submitted my data and was expecting the results within some minutes. To my surprise and also to the surprise of fellas working there, my results wouldn't come out foe more than 2 hours.......After the through labourious scanning and listing it was found that I had forgotten to add the end card to the programme which used to end the Programme ! And my calculations were getting repeated and repeated and repeated like our Programmer in the Joke !!!
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Data integrity means the security and the accuracy of the data.  \n\nData redundancy means data that is useless because it is repeated unnecessarily.
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Only if the disc is rewritable.
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Popular computer lore gives this credit to Admiral Grace Hopper, an early computing pioneer:\n\nhttp://en.wikipedia.org/wiki/Grace_Hopper\n\nCheck out the picture here:\n\nhttp://en.wikipedia.org/wiki/Image:H96566k.jpg\n\nIt may or may not be true, but it is usally attributed as the first "bug".
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They save duplicating code. That also means that once you get the loop code correct you don't have to test other duplicated copies of it for errors. \n\nIt also makes it easier to structure the program because the details of the loop processing are in one place.\n\nThey shorten the program so that it is easier to scan when bench checking.
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this probably means the file was corrupted during copy, try to find another copy that's ok, if it's something u download, u'd have to download it again, sorry..
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Faster more efficient reproduction - no suurprises
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Well, it sounds like the program is trying to move some structures from the original to conform with what it expects, and finds that it can't.  Then it writes them as original.  Probably has something to do with the copy protection on the original disks.  If it works, use it would be the best advice.