What is an ROA from IRS?

Can you clarify for me what exactly an ROA from IRS stands for? Is it a specific type of form or document that individuals or businesses need to submit to the Internal Revenue Service? If so, what information does it typically require and what purpose does it serve in the tax filing process? Is there a specific situation or scenario where an ROA from IRS would be particularly relevant or required? Thank you for your help in understanding this concept.