A financial invoice is an official document that outlines the terms of a transaction between two parties. It contains a detailed list of the goods or services provided, as well as the cost. It also serves as proof of payment and is used to track finances for both businesses and individuals. Invoices are important documents for any business, as they provide legal protection in case of any disputes. They should always be drafted carefully and accurately, ensuring that all details are included and have been agreed upon by all parties involved. Being able to effectively manage invoices can help to ensure the success of any business.