From the Internal Revenue Service

Starting a new business?  Having a good understanding of record keeping, business income and how to figure profit or loss is fundamental. Even if you use accounting software and think you’ve got a handle on it, it is important to understand some basic concepts. A good source is IRS Publication 334, Tax Guide for Small Business.

Yes, it’s a “tax guide” and federal tax topics are covered, it is the IRS after all. But starting with the section on business income and continuing through the section on net profit or loss, the information in this guide helps you make sense of your accounting software and other financial records.

For more tax and accounting information for small business, check out the IRS Small Business and Self-Employed Tax Center.

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