Imagine you have two pieces of paper with different things on them. You want to make them stick together so you use glue. But in order to make sure the glue sticks properly, you use a special machine called a fuser.
In the world of computers, a fuser is a part of the printing process. When you print a document, the printer puts ink or toner on the paper. The fuser is what makes the ink stick to the paper.
The fuser is like a hot roller that melts the ink or toner, and then presses it into the paper. This makes it stay on the paper and not smudge or rub off.
The fuser is also important for duplex printing, which means printing on both sides of the paper. After the first side is printed, the fuser heats up again and makes sure the ink or toner on the first side is dry before printing on the other side.
So basically, the fuser is the glue that makes sure the ink or toner stays on the paper, and prints come out looking good as new.