Remember the switch from 16-bit computing to 32-bit computing?  We moved from computers that could access 1 megabyte to computers that could access 4 gigabytes.  We increased our memory capacity by about 4,100 times.  As big a jump as it was, it was actually conceivable.  I’d worked with, and overflowed, 32-bit quantities.  Face it, four billion just isn’t that big a number when you’re working with computers these days–not when the smallest drive I could find at Fry’s the other day was 10 gigabytes for a whopping $80.00.  No, four billion is chump change.

So then, just how much bigger is 64 bits?  That is, if a 32-bit computer gives us access to 4,294,967,296 bytes of memory, how much memory could a 64-bit computer access?  Does the term “16 exabytes” mean anything to you?  That’s 18,446,744,073,709,551,616 bytes–four billion times the memory that you can access with your brand new Pentium 4.  We geeks have a term for that much memory.  We call it “a shitload.”

Not that I expect computers any time soon (not within the next couple of years anyway) to have that much memory installed.  I do expect, however, to see servers in the next couple of years that have at least a terabyte (one trillion bytes) of memory installed.  Even that is an astonishing number.  A terabyte is the amount of data stored on the disk drives of 50 of today’s typical personal computers.  All in RAM and instantly accessible.  This has some interesting, exciting, and even frightening implications that I will expand on in the future.