It's been two years since the Affordable Care Act was signed by President Obama. Since then, our health care system has improved in many ways. Some of the biggest changes include:

• Parents who get health insurance through their jobs can now have their children covered by their employer-provided insurance until they turn 26
• People with pre-existing conditions who cannot get coverage from insurance companies can now sign up for pre-existing condition plans
• Insurers can no longer charge copayments for preventive services for women, such as mammograms, pap smears, and well-child visits
• Insurers aren't allowed to drastically raise premiums without justification

To learn more, click here to read the statement made by Secretary of Health and Human Services Kathleen Sebelius to mark the occasion of the two-year anniversary. Click here to see a timeline of changes in the health care system that have taken place up to now and to see what will change in the future.