Let's say you don't have a UPS (I do).
But let's also be a bit more specific. In additional to the computer just sitting there on but not being used, let's say you have saved your work and went off to do other things. And now you lose power!
Now it will not have been shut down in the usual Start > Turn off computer > shut down. I'm guessing RAM would not be cleared and programs would not be closed. Is this serious? Does it matter? What differences will it make?
And what else might not be done?