Re: Ada a fourth generation language?

["Robert I. Eachus" <rieachus@attbi.com>]

Nick Roberts wrote:


> It is a fact that the earliest electronic programmable computers were
> programmed by arranging pegs in holes in certain circuit boards.
> (Programming all 10MB of Internet Explorer would presumably have taken a
> long time. :-)


I'm curious about which computers you had in mind.  The ENIAC used 
rotary switches for programming, but theoretically patch panels for 
arithmetic constants.  (A patch panel is a board with lots of holes, and 
you insert wires with plugs on them. Individual patch panels can then be 
stored and swapped.)  The reason I say theoretically is that ENIAC had 
enough electronic registers that it was more efficient to copy any 
constants into registers which could be accessed much more quickly.

The IBM 403 Accounting Machine, and later models used plugboards.  See 
http://www.columbia.edu/acis/history/407.html for photographs of an IBM 
407 and someone programming a plugboard.  IBM later introduced a 
"programming language" RPG, which almost directly mapped to the 
plugboards but was used on real computers like the IBM System/3.

There were early computers that used pegboards not wire plugboards for 
programming.  The only one I remember was the Burroughs E101.