Yes, the FCC still maintains a no call list. If you have registered your phone number in the past, it is still on the list.
Many of us are getting bothered by more and more sales calls, calls claiming to need to fix our computers and claiming to be about our credit, etc. Unless you have dealt with one of these companies and approved calls, and if you are on the no call list, these calls are illegal. Also, often they now spoof the phone number the call is coming from so if you have caller id (which we all do on cell phones) it appears to be a local number and you answer. When they are spoofed, the person who has the number they used will have no idea their number was used. I regularly get calls from people saying I just called them, and I had not placed a call all day and definitely not approved these calls from my number.
The web address for the FCC no call list is www.donotcall.gov There you can get put on the list, check to see if you are already on the list and also report calls that you should not receive. To report calls, you will need the number it showed calling from and the date and time.
The list does work as the government recently sent a person to prison with a large fine for bunches of violations of the do not call list.