Financial Accounting allows you to keep track of different expenses and different sources of income. It does this by assigning different financial codes to each area you want to track.
So for expenses there might be different codes for fuel, lunch, heating, office rent and so on, and therefore your accountant can advise how much is being spent in each area.
For revenue there might be different codes for income from your website, income from your shop, income from goods, income from services and so on, and again, we can then advise on where you are making more money and where you are making less.
So Financial Accounting helps give you a good picture of what you are spending your money and what is making you money.