The File Stream Object allows you to open multiple files at once without ever once loading them into memory. Once the files are open, you can get and set individual characters, shorts, integers, floats, doubles, and strings however you please.
This is especially useful for dealing with very, very large files that would take quite a long time to load into memory, and would then be using a lot of memory. Because this extension never actually loads the file into memory, you are safe to quickly open and save large files. This does not mean that it will accelerate fastloops to go through large files