The dictionary describes a budget as 'planned expenses and a program for financing them'. This means that knowing how much you're going to spend and when you're going to spend, and from where you'll spend is the most important piece of your financial planning. 

You don't start with the income you have or think you'll have to create a budget, you begin with the expenses you know you have and expect to have. The difference is an 'earn more than you spend' approach to managing all your financial decision-making, as opposed to 'spend less than you earn'.

The system of managing and planning cash flow from this perspective is the basis for managing personal finances, business finances, short term financial projects, or long term planning for financial increase!