An accountant is a general term for a formally educated professional who helps maintain financial records, analyzes financial records, and/or make sure taxes are paid properly. They may or may not be certified as a public accountant (CPA). An accountant has thorough knowledge of cash flow, owner's equity, balance sheets, chart of accounts, etc. and their effects on a business.
A CPA (Certified Public Accountant) is a professional designation that's regulated by states. CPAs must maintain a certain amount of professionally logged hours per the state they are certified within. These logged hours help establish a measure of how reputable they can become and the levels of practice they may be offered to resolve. To become a CPA, you must pass the CPA exam. Not all accountants take the exam and not everyone who takes the exam passes.
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A bookkeeper cannot do the same work as an accountant or a CPA, BUT an accountant and a CPA can do bookkeeping.
An accountant cannot do the same work as a CPA, BUT a CPA can do accounting.