Health insurance helps cover eligible healthcare expenses according to the terms, benefits, limitations and cost-sharing requirements of a specific plan.

A premium is the amount you pay for your health coverage, usually on a monthly basis.

A deductible is the amount you generally pay for covered services before your plan begins paying for services subject to the deductible.

A copay is a fixed amount you may pay for a covered healthcare service.

Coinsurance is generally a percentage of the cost of a covered service that you pay after meeting applicable deductible requirements.

It is the plan's limit on your costs for covered services during a plan year, subject to the plan's rules.

They differ primarily in how provider networks and out-of-network care are handled.

Eligibility depends on your circumstances. HealthCare.gov provides the application and eligibility process for Marketplace coverage.

You may be able to enroll during a Special Enrollment Period if you experience a qualifying life event. Medicaid and CHIP have separate eligibility rules.