Book excerpt: It is very easy to control and manage business when a business is very small. Hence the entire double entry account is kept in one book called a ledger.As the business grows and expand it would be impossible just to use one book as the large number of pages needed for a lot of transactions, could be very difficult to handle.To solve this problem of getting difficulties in handling, the bookkeeper should use more books. Through this all similar types of transactions are handling together and have a book for each type.Remember not to mix together transactions which are different from one another. Therefore, the books which are used to record all similar transactions on a first time before posting to the ledger account are called books of original entry.