Definition of write off and write back ? URGENT

1.A reduction in an individual's or a company's income as the result of an expenses. For example, an unpayable credit sale may be a write-off for the creditor, especially if the debtor declares bankruptcy. The bankruptcy means that the debtor is unable to pay the debt, which results in a loss of income for the creditor.

2.To take an asset entirely off the books because it no longer has any value.If an accrualbasis taxpayer has taken money into income when bills were sent out to customers,but then some of the bills became uncollectible, the taxpayer may write off the uncollectible ones as a deduction against income. Financial institutions are required to write off loans when they become delinquent by a certain amount.

3.write-back

• in Finance the process of restoring to profit a provision for bad or doubtful debts previously made against profits and no longer required.

Correct contribution towards CCI. Great Linesh......

 i want to pass on the discount to the customer through credit notes can it be called write off ?

Those bank accounts are called techniquelly write off.?

What is the meaning of this?

 What is the method of calculating these accounts?