The instructions are kind of in the video, but here they are again. This is video sensing, so scratch has to open your webcam, and take a live video. It will then sense the movment in the video, and if it thinks there is a certain amount of movement beside a sprite, then it activates the code. In this case that code is to play a sound. I know this is a very simple code, but I'm new to scratch, and wanted to do something for my friend abigail, whose birthday is tomorrow. I also made another short video for her b-day, called "happy birthday abigail," if your intrested in seeing that one, but I don't know why you would be.