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Why 140 chars is like 48K

Tuesday, June 23, 2009 by Dave Winer.

I love telling stories, especially ones with happy endings.  

Once upon a time, way back in the early 80s, a young man (me) had written a program called ThinkTank. It ran on the Apple II, which only had 48K of memory -- not very much when you consider that an average PC today has 1 gigabyte -- or 21,845 times the memory if you can believe that! 

That's like comparing a single 140-char tweet to the Library of Congress. 

The Apple II had an infintesmally small memory, but its disk was a little larger. So the operating system I used, the UCSD P-System, did "overlays," which allowed big chunks of code to stay on disk until they were needed. When code in an overlay was called, the OS would throw out another chunk of code and replace it with the one you called. So, in the worst case, if a command needed code in two overlays to solve a problem that involved looping, the disk light would stay on for a long time while the computer "thrashed" out the answer.  

This isn't unlike the way an Amazon Kindle keeps part of your library on its computer and part of it on the Kindle itself. When you want to read one of the books on their computer it just downloads it again, replacing something you haven't read in a while. 

This business of writing code in overlays was very taxing to the developer, because thrashing wasn't very good for the usability of the code, so you're always moving code between overlays, or making a copy of an often-used routine, all to prevent the disk light from coming on and thrashing the app (and its user) to a standstill. 

This clever code-writing is a lot like writing 140-character tweets today. You delete and abbreviate, throw out important ideas, all to fit into that tight little space. And then your readers, like the disk light, thrash with confusion, and think you're a fool, because you have to be a genius and a mind-reader to figure out the gibberish you wrote to fit in 140. Oy!! 

So, with the app in the Apple II days, it was often too much trouble to add the feature. With Twitter, it's often easier just to say nothing. And that's not the goal of blogging, macro or micro. The goal is to provide a platform for saying what you have to say, not for not saying what you have to say!  

Anyway, the Apple II story had a happy ending. It was called the IBM PC. Instead of 48K it had 640K. So when I recompiled my app for that machine I just threw out the overlays and let all the code reside in memory and the thing ran like a bat out of hell! I was finally able to finish the features I wanted, and instead of thinking the program just had potential, people loved it, and it sold, and we raised money, and everyone was happy.  

The End. 

Update: If 140 is too little, what's the right number?