Self balancing ledgers

1.The Debtors account you talking about is kind of group account & consist of balances of various debtors.Thus Debtor A from whom amt is receivable will be shown in Debit side & say an advance has been received from Debtor B then it will have Credit effect on Debtors(group) account.

3. It may happen that you sell some goods to debtor A & also purchase some other goods from Creditor A.Thus amt is payable & receivable to/from Mr A and so these amts are written off against each other as adjustment:

Creditors account Dr.

      To Debtors account

thanks 

What exactly is GLA A/c?(genral ledger adjustment account)

it is written in place of  SalesA/c etc

Yes its kind of sales account because to make an entry you need to give Dr & Cr(to 2 different accounts) as per rules of double entry system.Thus this is a notional account created with name GLA

Thanks a lot :)

why the same entry why cant

debtors A/C

      To creditors A/C