Hey, I'm only 14. I still have lots to learn. Anyway, I was under the impression that the larger the space on the disk, the slower read-write speeds.
No, it's the other way. Read- Write speeds are given as an average for random seeks. Not for the time it takes to read and write the whole disk. A HDD is considered to be a virtual random access device. That is because the head can skip over tracks and find the right sector. It does not have to read each track to find its way. Internally it has a map of the layout of the disk and the logic knows how far to step the head to find a specific sector.
But, more data per track means it can take longer to find a sector if you only have a single head. So Multiple platter drives and multiple heads help improve this.
We are not yet finished with hard drive technology. There is still more to come. What they want next is a solid state head that is much smaller that present designs and can read several tracks at the same time. This will improve transfer rate and seek time.
Petabyte is maybe on the horizon.