What are corrupt files?

Thinking of Mada_Milty and great explanations

I've often heard the term corrupt files, but when it came down to discussing what they are, no one could tell me. Are they hardware or software problems? Both? Is it a catch all term that refers to a lot of different kinds of file problems?

Thanks in advance!
abri

 

Corrupt files are files that are damaged.
They can get damaged by hardware (When you download something it may become corrupt because of some hardware problems)
Or they can get damaged by software (Wiruses, or some bugs in a program)

 

Wiruses?

is that a super virus or something

 

That covers most of it. The mechanics is pretty simple, a file can have part of it missing. If it is a word document that you are writing (as in a book) a partial can be a big deal compared with a complete loss. Most cases it is the end of the file that is lost, because the beginning is what is kept track of.

Another mechanism is simple scrambling of bytes, the characters have been randomized, or pseudo randomized if it is an encryption technique gone wrong. In this senario you have the same number of bytes you started with. Software can detect scrambling of data by using checksums, you add all the bytes together, keep the low byte and compare this number with one stored in the file. Checksums are a routine method of detecting whether you got a packet intact, if it is bad then the computer requests a resend of the packet.

Hard drives routinely scramble data in both methods when they are dying. Murphy, being the pesky fella he is, can usually come up with new and aggrivating ways of trashing your data when you think all your bases are covered.

 

how about this;
A corrupt file is a file that contains something that it should not contain, or it does not contain something that it should - either of which would render the file useless.

 

At the level we're talking about, it's all bytes. One's and zero's, so the mechanics of the crash is somewhat important. Sometimes it doesn't even matter, if the byte isn't important, so the file is technically corrupt, but it's no big deal.