Prepaid refers to services paid for in advance. Examples include tolls
As applied to accounting, accrual describes the concept (known as accrual accounting) where a revenue or expense is not recorded (recognized) at the same moment in time as the related cash inflow / outflow.
For example, on December 30, 2001, a company delivers a product to a customer who will pay for that product 30 days later. Assuming the fiscal year ends on December 31, the company discloses that revenue in 2001 Income Statement even though it will get paid during the following fiscal year.
Similarly, the sales representative that sold the product is entitled to his or her commission at the moment of sale (or delivery). That means the company will record an expense (Salesperson’s Salaries and Commissions) in its 2001 Income Statement, even though the rep will actually get paid at the end of the following week, in January, 2002.
Unfortunately, the term accrual is also often used as an abbreviation for the terms accrued expense or accrued revenue, items which may share a common name but have a different economic / accounting characteristic.
Accrued revenue is a receivable for other revenue. It is disclosed separately on the balance sheet primarily to allow investors to differentiate receivables from core operations from receivables from peripheral operations.
An accrued expense, on the other hand, is a liability with an uncertain timing or amount but where the uncertainty is not significant enough to qualify it as a provision.
For more details, pls visit
http://en.wikipedia.org/wiki/Accounting_methods