ACID of 4 rule is composed of (Atomic teen Consistent, Isolated, and Durable) that put together, it's a transaction concept can't find:

a) Atomic: means all or nothing
if the transactions of the several change to be formed, all of which must be successfully performed, or whether any changes should be opportunity to apply the final flourish.
for example, the transfer amount X from an account. to another account, consider. In this mode, the X rial from the account person, the deduction, and X rial to another person's account, will be deposited. If the inventory account. have the X rails ... should not be a sum from this account can be deducted. The first stage failed. so the whole operation is canceled. Also, if the account is the recipient of the package is also not a sum of from the account of the first fraction be in this case also, the entire transaction should back eat.

b) Consistent or integrated
here is the consistency in addition to applied the constraints, meaning the information that, immediately after the end of the transactional system can be downloaded and read.

C) Isolated: enclosed
if multiple transactions at a time with running time. thus the final state of the transaction, one after the other, are run should be one.

d) Durable: lasting
if the end system transactions to announce. this case means 100%, written information in hard disk should be.