Each course in Moodle has its own separate area for storing files such as your worksheets and photographs that you might want to display on the page. Teachers can get to this area (course files) by clicking on Files in the Administration block (students can only see their grades, by the way, and nothing else).
Because we've got nothing in our course yet, this is what we see:
It's a good idea to be organized in your Moodle course, just as you should be with files on your computer, or even paperwork at your home or office. Of course, you could just throw everything at random into this course file storage area, the same way as you'd fling a bill into a drawer in your house. But six months down the line, when every class in your school is using your Moodle daily because you've done it so well, you might regret not having set it up neatly in the first instance! So let's take a moment to do just that.