Mo Henry is not a person, it is a technical term used in the film and video industry. Remember when you watch movies or TV shows, and the scenes are filmed from different angles? Well, when the movie is being edited together, the different shots need to be matched up so they look like they were all filmed at the same time and place.
This is where Mo Henry comes in. Mo Henry is a technique used by editors to make sure that all of the shots flow together seamlessly. It involves a person who creates a special kind of marker, called a "match move marker." These markers are placed on different objects in each shot, and the editor uses them to align the shots and make sure everything looks like it's happening in the same place.
So, imagine your teacher takes a picture of you standing in front of the classroom, and then takes another picture of the same classroom, but from the back of the room. If she wants to put both pictures together to make one big picture, she would need to use Mo Henry to make sure that both pictures match up perfectly. She might put a little sticker on your nose in the first picture and then use the sticker to line up the second picture so that everything lines up perfectly.
Mo Henry is just one of the many tools that filmmakers use to create the movies and TV shows we all love to watch.