There are different income ranges for different tax filing statuses. Taxpayers who file their returns as single have a set of income ranges that correspond to these seven percentages differently from married couples who file joint returns. Heads of household and married couples filing separately also have different income brackets to accompany the tax rates.
It's also worth clarifying that these tax brackets apply only to your taxable income, which differs from your salary, adjusted gross income (AGI), or other income metrics. In other words, just because your salary is $75,000 doesn't necessarily mean you'll be in the tax bracket that corresponds with this income.
Your taxable income is the number left after subtracting all your adjustments and deductions. If you contribute to retirement accounts, pay mortgage interest, donate to charity, or pay lots of state and local taxes, your taxable income can be significantly less than the amount of money you actually bring in.