IO Systems, Hard Drives and Files/Folders

Alright this week, we learned all about how I/O systems are basically everything connected to a computer. I/O stands for input/output. Signals to I/O devices are routed through something called a bus. I/O device signals can be handled via polling or via interrupts... there's a third option but, I already forgot what it was. Hard Drives are an I/O device but, they are special in that they can contain persistent data unlike the random access memory that we have been using to load programs and whatnot. We learned a lot about how spinning disk hard drives work which is a lot less relevant now that SSDs are almost everywhere but, it's still cool to know and shows exactly how insane some of this hardware engineering is. The fact that we can pull bits from a disk rotating at a ridiculous speed is nuts. Oh we also learned about how drivers make all these I/O devices work and Windows kinda sucks because it tries to support ancient I/O drivers for devices that no one has anymore.

Finally Files and Folders. We learned about how File names are just Ids and the exact format of how files and folders are stored with iNodes. We learned the functions that modify files like `unlink` `open` etc. Interestingly enough these verbs are the same in node.js' API. We also learned how read/write access for files works. We learned how about how file partitioning works as well but, I don't understand it well enough yet to regurgitate it here.