At the very basic level of personal finance, you should understand the need for, and value of, a budget. A budget or spending plan is a road map for telling your money what to do each month. At its simplest, a budget lists how much income you have compared to what's going out. Creating a detailed and written budget allows you to make smarter decisions with your finances on a daily basis. When you're faced with spending money on something, a budget requires you to stop and think about the purchase. You realize that by spending money in one area, you won't have to spend elsewhere.
When you create a budget, you begin to see a clear picture of how much money you have, what you spend it on, and how much, if any is left over. Ideally, you'll have a surplus left over which you can use to save for retirement, build up your emergency fund, pay down debt or apply to other financial goals