I know there are a lot of encryption programs available, that I would guess use different methods for encryption, and thus have different types of output files (.fve .tc .cha .dmg (bitlocker, truecrypt, challenger, ect.)), but if someone didn't know what the file was and just looked at the data, what would it look like? Does it just look like random bits, or can you still pick out a pattern? If it does look random, how is it if I moved the encrypted file to another computer, the other computer can tell it's a file, and is able to decrypt it (how would it even know where to start or stop, if it all looked random)? Also, how is the structure affected by encrypting files twice, using the same method, or a different one? Thanks for any help, and if you know any books or site about encryption for complete idiots, I'd appreciate it!