The Social Security Trust Fund is a government account that holds surplus funds collected from payroll taxes under the Social Security program. This program provides financial support to retirees, disabled individuals, and survivors of deceased workers. The trust fund is crucial for ensuring that these benefits can be paid out even when current tax revenues are insufficient. The trust fund is divided into two main parts: the Old-Age and Survivors Insurance (OASI) Trust Fund and the Disability Insurance (DI) Trust Fund. When the funds are needed, the government can borrow from the trust fund to cover benefit payments. However, as the population ages, concerns about the fund's long-term sustainability have arisen.