Not only am I a newbie to the above, but the only thing I know about Apple is Apple TV. Anyhow, I was given a MBPro, vintage 2011 and was able to click on what's on this Mac and came up with Yosemite for an OS. I am a Windows 10 user and have been for many years so I am not a total loss around a computer. Actually, I don't really care what's on this notebook, but what I'd like to do is wipe it clean and start from scratch and learn how to set it up and use it. I did some reading and put the serial number in to the site that ID's the laptop and its' a 2011 Core I5, 8GB ram and 1 TB hard drive. It would seem as though it would run the Sierra OS. The machine seems to run fine, bit I'm not interested in fixing it and running with all the junk that's on it. I would appreciate some advice as to what to do next and the simplest way to get a new clean install of the newest OS and start from there. I do have a spare WD Passport drive to back up the laptop up in case I totally trash it. Thank you. P.S. In that no one has replied, I apologize if I used the inappropriate forum to ask such a question. Just wanted a little push in the right direction.