Okay kiddo, do you remember using a regular camera with small, rectangular film inside? Well, medium format is kinda like that, but bigger!
Instead of small, rectangular film, medium format cameras use big, square film that's about the size of your hand. This bigger film lets photographers capture more details and a higher quality image.
It's kinda like having a bigger piece of paper to draw on - you can fit more details and colors than on a smaller piece of paper.
But, since the film is bigger, it means the camera has to be bigger too. You might have to use two hands to hold it!
Also, the process of developing and printing the film can be a bit more complicated than regular film. But, some photographers think it's worth it for the high quality images they can capture.
So, in summary, medium format is like having a special camera and film that allows photographers to take really detailed and high-quality pictures.