That question was asked by Jimmy Kimmel of random people, here is the video:
The answer: They are the same thing.
The bill started in the House of Representatives as the “Service Members Home Ownership Tax Act of 2009” on 9/17/2009. It passed the Senate as the Patient Protection and Affordable Care Act on Dec 24, 2009. House agreed to the Senate Amendment on March 21, 2010. President Obama signed it into law on March 23, 2010.
The term ObamaCare was coined in 2007 by opponents during the election. It was first mentioned in a political campaign by Mitt Romney to describe the health care plans of his opponents, “It’ll be what’s known as Hillarycare or Barack Obamacare, or whatever you want to call it.”
By 2012 ObamaCare had been used by both supporters and opponents of the law. President Obama even said of the nickname, “I have no problem with people saying Obama cares. I do care.”
The United States Supreme Court upheld the law, and the amendments, on June 28, 2012.
Patient Protection Act (http://en.wikipedia.org/wiki/Patient_Protection_and_Affordable_Care_Act)
National Federation of Independent Business V. Sebelius (http://en.wikipedia.org/wiki/National_Federation_of_Independent_Business_v._Sebelius)