What is balancing of account?

Balancing an account is when you add up assets, liabilities, and owner equity and put them into the equation...

Assets = Liabilities + Owner Equity (often called Stockholder's Equity).

The reason for doing this is to spot and correct errors. If this equation has equal numbers on both sides, the account is balanced and the accounts are most likely correct (you can still have a mistake with balanced accounts). If it is not equal on both sides, there has has been a mistake and the transactions need to be looked at more thoroughly.