The 'Affordable Care Act', 'Obamacare', and 'The Marketplace' are all exactly the same thing. It is simply an online shopping mall (Healthcare.gov) where regular people can buy highly regulated, legal health insurance.
The Magic of Subsidies
The best part about the Marketplace is the 'Advance Premium Tax Credit' (a subsidy). If you make between $20,000 and $55,000 a year, the government will pay the insurance company directly to lower your monthly premium. A plan that normally costs $400 might only cost you $40.
No Discrimination
It is illegal for any plan on this marketplace to deny you for a pre-existing condition. They cannot charge you more because you are sick, or because of your gender. Everyone pays based on age, zip code, and smoking status.