True" in this tutorial, we're going to be editing and sending a PDF file. So, we're going to take our test PDF and open it up. On a Mac, you can see that the Preview app opens up. Here we have a PDF file and I cannot edit this document. This is like a digital print. PDFs are like digital prints, you cannot open them up and edit them unless you have special software like or another way to actually edit PDFs. In this case, on the standard configuration, we don't have a way to do that. But, we can make notes by using the mark-up tool. So, if I choose this icon which is a circle with sort of a pen-looking icon in it, I'm going to see the mark-up toolbar and we have a number of different tools that we can use. Here we have a tool that will allow me to type on the picture. Let's say I wanted to make some notes. The way I'm going to use this text feature is that I can change the size of the text by selecting one of these blue circles. And within the blue circles, I find an arrow that will allow me to increase the length or the height of the text. So, I can make it quite long, I can make it tall and adjust it by using the sidebar. My selection is being made by navigating to right where these blue circles are, and that is how I'm going to change the shape of the text. So, in order to make a change within the text and change this writing, I am going to click down with the mouse or trackpad and select detect inside of the [text]. And I'm gonna wait till it turns blue,...