 Hi, this is Dr. Don. I want to take a couple of minutes and show you how to make backup copies. So when you're working in our studio, you can always refer back to the originals. A couple of ways of doing this. One of the first ways is just to make a copy. And to do that, you can click by the name of the file. I'm using this first one there. Click it. And then I want to go to More, Copy. You can see it offers it up. I can change the name right here if I want, or I can just keep that. So I'm going to keep that and show you how to change the name later. So you can see we've created a copy of the original of that data worksheet. Now, if I want to change the name of any of these items in here, I can just click that file and go to Rename. And I'm going to get rid of a copy of, because I want it to sort alphabetically. And what I like to do is just put my initials on the end, dash, d, w. And that makes a copy that way. You can see now I've got the original up here, and I've got my copy there. And if I just sort those on name, you can see they're all sorted together. And you can see I can see the one I want to work on. Another way is to do a file save as. I'm going to open up this other worksheet, the graphing data worksheet. Click on its name, and it's open over here in the source editor place. And I want to go and just select on File, Save As. And then I can click my cursor where I want to insert. Let's place it over there, and I'll sort dash, d, w, that way, and then Save. You can see now I've got a copy there. So those are a couple of ways that you can do a file save as or make a copy of a file. You can also rename files. For example, if I click on this file and click on Rename, then it offers it up. And I can, for example, maybe I want to put my middle initial. Click OK, and it's renamed the file. So I hope this helps.