Define the major organizational hierarchy elements within the Financial Accounting module and explain the relationship between each of them.

The hierarchy, from the highest organizational unit to the lowest, is the Client, Chart of Accounts (COA), Company Code and the optional Business Areas (BA). Two other optional areas include the Dunning Area and the Credit Control Area (CCA). Credit Control Areas come above the Company Code, and Dunning Areas come below the Company Code. There is only one Client and its values are the same across all Company Codes that are attached to it. Every Company Code is a legal independent entity. Business Areas can be shared among Company Codes (many-to-many relationship) and they are used for internal reporting purposes. Each Company Code is assigned a COA. The COA may be the same for multiple Company Codes, but each Company Code may only use one COA.