The IRS allows all taxpayers who do not itemize deductible expenses to claim the standard deduction. The government sets the standard deduction amount every year for each filing status. For example, in 2014 the government authorized a $6,200 standard deduction for single taxpayers, $9,100 for those who file as head of household and $12,400 for married couples filing a joint tax return.
So, if you are a single taxpayer who earns $100,000 during the year, the standard deduction reduces your taxable income to $93,800. However, this amount is subject to further reduction by other allowable deductions you claim.