Scalability

When I started as a computer professional, we used minicomputers.  They were called "mini" because they were only as big as two or three refrigerators, and four times as noisy.  They had to be installed in special climate-controlled rooms, with raised floors for all the cabling and air conditioning.  We used to run what we called application programs.

Then the whole world went to personal computers. These could fit on a desk, with plenty of room left over for a pencil or a paper clip. The computers themselves weren't so big, but you needed room for boxes and boxes of floppy disks. And these disks contained applications. Not application programs. Just applications.

Now I carry the equivalent computer power in my pocket. One in each pocket, actually. We don't need floppies. Everything's in The Cloud. And those programs? Now they're just apps.

Next I suppose everything will be implanted surgically.  The user interface will be just to think of what you want. Of course, it will be hard to drive with all the "Updates are available" messages popping up in our heads.  But so what?  They'll drive.  There'll be an A for that.