You know how sometimes you want to draw a really big picture, but your paper is only so big? Well, computers sometimes have the same problem. They can only save files up to a certain size, like a piece of paper.
But sometimes people need to save really BIG files, like really, really big pictures or videos that are longer than a few minutes. That's where large file support comes in. It helps computers save and work with really big files.
Think of it like having a bigger piece of paper, or using lots of pieces of paper and taping them together to make a really big canvas. Large file support lets you use more space on your computer to make bigger, better files.