SSDI stands for Social Security Disability Insurance, which is one of the disability programs administered by the Social Security Administration. It’s a type of benefit that you qualify for by having worked enough and paid in enough to Social Security taxes to receive benefits.
It is typically considered to be a better benefit than Supplemental Security Income (SSI), because you may receive more in monthly benefits. The amount of your monthly benefit payments is based on your previous earnings. You may also qualify for Medicare in addition to/or instead of Medicaid. Some individuals may be eligible for SSI and SSDI benefits.