Imagine a big metal box with a small window on the top. Inside the box, there is a reel of photographs that move really fast when you turn a handle. As you look through the window and turn the handle, the moving pictures make a little movie!
This is what a mutoscope is. It was a machine that was popular in the early 1900s before movies had sound. People would pay a penny to see a short film or glimpse into what looks like a flipbook come to life. The mutoscope was a fun way for people to enjoy movies before they had sound and before video screens were invented.