What is the difference between the accrual accounting and cash accounting?

The Cash Basis of accounting reports only transactions that have been completed in the current reporting period - or - what has "hit" the checking account (assuming all funds are deposited and disbursed only from that account) - The Accrual Basis of accounting reports all transactions that the entity has entered into and includes the asset, liability, income and expense related them.

In addition, the Cash Basis of accounting is considered OCBOA (Other Comprehensive Basis of Accounting ~ Other than GAAP) and the Accrual Basis (when implemented properly and fully) is considered GAAP (Generally Accepted Accounting Principles).

EDIT - The Accrual Basis is more desirable from a user's standpoint as it includes transactions that may exist were completed after the report dates that were initiated prior to the report date. It is generally more complete and more reliable than the cash basis - however, that does assume that the person preparing the statements has expertise of, not simply a cursory working knowledge of, GAAP and the accrual basis. For example, a set of financial statements printed out of QuickBooks are not necessarily GAAP compliant (or correct) although they may appear to be at first glance or to a layperson.