From the Summary: "The military retirement system is a government-funded, noncontributory, defined benefit system that has historically been viewed as a significant incentive in retaining a career military force. The system currently includes monthly compensation for qualified active and reserve retirees, disability benefits for those deemed medically unfit to serve, and a survivor annuity program for the eligible survivors of deceased retirees. The amount of compensation is dependent on time served, basic pay at retirement, and annual Cost-of-Living-Adjustments (COLAs). Military retirees are also entitled to nonmonetary benefits including health care benefits, exchange and commissary privileges, and access to Morale, Welfare and Recreation (MWR) facilities and programs. Currently, there are three general categories of military retiree-active component, reserve component, and disability retiree. Active component personnel are eligible for retirement (i.e., vested) after completing 20 years of service (YOS). Reserve personnel are eligible after 20 years of creditable service based on a points system, but do not typically begin to draw retirement pay until age 60. Finally, those with a disability retirement do not need to have served 20 years to be eligible for retired pay; however, they must have been found unqualified for further service due to a permanent, stable disability."
CRS Report for Congress, RL34751
Congressional Research Service: https://crsreports.congress.gov/