If you exceed the standard deduction, filing your return gives you the chance to reconcile your tax bill with the IRS. You might have overpaid through paycheck withholdings, entitling you to a tax refund you can spend how you please. There's always a chance you underpaid.
You'll file using Form 1040. You can check out software like TurboTax to help. Make sure you have all of your deductible expense receipts, charitable donations, business expense receipts, and more handy.
It's a progressive tax system. Meaning the higher levels of taxable income, pay a higher tax rate. These rates are adjusted annually for inflation.
Slowly work through the 1040. You'll calculate your total income and total dedication. Then you'll have an amount that you owe. If you prepaid, you're good. If not, you'll have to send the IRS a check.
You can use tax deductions and tax credits to lower your taxable income. There are some common deductions you may be eligible for.