Tax dependency refers to the relationship between a taxpayer and a dependent, typically a child or relative, for tax purposes. A dependent can help reduce the taxpayer's taxable income, leading to potential tax benefits such as credits and deductions. To qualify as a dependent, the individual must meet specific criteria set by the IRS, including age, residency, and financial support requirements. There are two main types of dependents: qualifying children and qualifying relatives. Qualifying children must be under a certain age, live with the taxpayer for more than half the year, and not provide more than half of their own support. Qualifying relatives can include older relatives who live with the taxpayer or receive significant financial support.