Today, everyone takes it for granted that you can type text into a computer and edit it on the screen. But this wasn't always such a commonplace activity. Indeed, it used to seem downright miraculous, as this 1982 passage by James Fallows in the Atlantic shows:
When I sit down to write a letter or start the first draft of an article, I simply type on the keyboard and the words appear on the screen. For six months, I found it awkward to compose first drafts on the computer. Now I can hardly do it any other way. It is faster to type this way than with a normal typewriter, because you don't need to stop at the end of the line for a carriage return (the computer automatically "wraps" the words onto the next line when you reach the right-hand margin), and you never come to the end of the page, because the material on the screen keeps sliding up to make room for each new line. It is also more satisfying to the soul, because each maimed and misconceived passage can be made to vanish instantly, by the word or by the paragraph, leaving a pristine green field on which to make the next attempt.
Computers have improved so much over the past three decades that it's hard to even describe the difference. The computer Fallows owned in 1982 had 48 kilobytes of memory. That was enough to store a few pages of text, but it would be too little to hold many modern webpages or even a single high-resolution photo. I'm typing this on a MacBook Air with eight gigabytes of memory — more than 100,000 times more.
And the comically underpowered computers people bought in 1982 were expensive. Fallows spent about $4,000 for his, which would be more than $10,000 in today's dollars. In contrast, my MacBook Air cost me about $1,200.
(Hat tip to Kevin Roose)