The main objective is to determine the company's profitability. Whether you are a lemonade stand or a billion dollar company, you likely have revenues and expenses. The profit and loss sheet lumps each revenue stream into a category. For example, product sales, advertising sales, and subscriptions might all be valid sources of revenue for a company, and the profit and loss sheet would pran accounting for the amount of revenue generated from each of those sources over a predetermined period of time, typically month by month over the trailing twelve months. The process is generally the same for expenses, and aside from a few small nuances, once you've got a full accounting of revenue and expenses, you'll be able to define profitibility. If you want more inforomation, you can check out this comprehensive guide I recently wrote: How to Create a Profit and Loss Statement + Free Profit & Loss Template