 Hi, this is Dr. Dunn. I want to talk a few minutes about the Run button, the Code Run button, or in this case we'll worry about the No Run button starting. Let's start the simplest way that you cannot see a Run button is if you've got your source window collapsed, like I do here. And to open it up, we just click on that to expand it, and now you can see we've got our Run button there at the top of the window. And of course, this little green arrow is the rerun, the code we just ran. If you've got a regular R script file, which just has an R, let me go over here, you can see here in the Run button, we've got a basic R script which just has the dot R. And that capital R is important. If your file name doesn't have an R, you will lose the Run buttons. And in this case, for example, I saved my student name and accidentally deleted the capital R, so this file, if I go to this one, you can see here that it's missing the Run buttons down here inside the code chunks. You've got the Run button up at the top, but we don't have the Run buttons in the code chunk here. And that's because we don't have that R in the file name, so you can just change the file name back. Another way you can lose the Run buttons in the code chunks is to accidentally delete your R code indicator up there. You can see as soon as I lose the R in the bracket, I put those back, I've got my Run button in that code chunk. So when you're pasting in code, it's awful easy sometimes to overlap that in the paste in and that will lose the R button. So again, in your code chunks, you need to have the R code and then you should see the green Run button here. Even without that Run button, I can run this code because I've got my file name properly just by highlighting it and go up here to Run and run the current chunk. So I hope this helps.