ReFS can support drives up to 1 yobibyte in size. A yobibyte is 1,099,511,627,776 terabytes. That is over 1 trillion terabytes. Holy crap.
So what! My new file system BeERFS can support drives up to 1 gazilajobilabytes. A gazilajobilabytes is 1,099,511,627,776 yobibytes. Just like M$'s system, it will likely be years before you see it and it really doesn't matter because no one can afford a new 1.5 yobibyte hard drive anyway.
At this point in time the yobibyte (or rather yottabyte depending on perspective but both are the same size) is the largest unit of measure in the binary system. It came into existence back in 2005. No idea what the next level after that will be but I do know it will be a number which is equivilant to the size of 10 to the 27th power. The yobibyte is 10 to the 24th power. Each successive size is an addtional 3 power from the previous. Starting with kilobyte which is 10 to the 3rd power.
Those figures are based on the International System of Units (or rather metric system) but, in reality, those are not 100% correct as the actual sizes are 10 to whatever power times a factor- such as 1.024 for KB, 1.049 for MB, 1.074 for GB, 1.1 for TB, 1.126 for PB, and so on.
Those factors come from the IEC.
The odd thing about all that is that we use the SI naming system for all the sizes but use the IEC math for the actual sizes. Not sure why that is.
This is what I'm referring to from http://en.wikipedia.org/wiki/Kilobyte