3D Technology in Doom

Hello,

surfing the net for about two hours, I do find everything about Doom, but my initial question isnt answered. I´d like to know how the 3D-technology in Doom works. AFAIK it is not polgonbased like Quake - i know the characters are 2D - but what about the levels itself ? How is the 3dimensional effect created ?
I´m not a programmer or 3D Designer so I do need it an answer in common language ;)

Its about a work for university in which I try to describe the step from Doom to Quake acording the 3D technology (the work is about perspectives in Videogames). My thoughts are that in Quake you can watch the surroundings from every point of it because its polygonal. I think I remember perspective distortions in Heretic when you when I looked up or down, don´t I ?

Thank you for helping !

Try this: http://en.wikipedia.org/wiki/DOOM_engine

Thank you, that was the information I was looking for. The german wikipedia got some information about Doom, but not the engine.

To be sure I understood the principle correctly: The effect of 3D Surrounding is created by moving 2D drawn walls in front of the Player, a little bit like a scenery ?
And because the textures on the wall are made up from vertical columns of pixels, the player can turn so the columns closer to the player are kinda zoomed in (resolution is lowered), the more away are zoomed out, so it looks like the wall is stretching on in 3D ?
And because of that you would get strange distortion effects if you would try to look upwards ? (you would need horizontal columns of pixels as well to do that properly, perhaps its like that they did it in Descent?)

I know this describes it very plainly, but as I mentioned, I need it that way to understand the principle (and get it explained to lecturers who have difficulties to operate their DVD-Player).

Thank you for pointing me in the right direction in the first place !

Can you briefly describe, what the Doom3 engine has to do with operating a DVD player?

1-Doom one, not three.

2-People who have major trouble with technology are sometimes referred to as people who can't even program their vcr. Sort of a joke.

Yes, it was a joke, sort of a lame one, sorry.
But... Could anyone try to explain the principle of Doom 3D graphics in simple words to a nonprogrammer ? Is ist all by drawing vertical columns on the floorlines and texture it ? And how are the vertical lines calculated ?

The information in wikipedia are quite good, but a little too technical.

It would be very helpful.

All wall were drawn vertically. All floors/ceilings were drawn horizontally. Everthing was re-drawn every frame. The calculations are perspective-correct (taking distance and angle into account). Yes it didn't allow looking up/down properly, and the original Doom didn't have that feature.

Levels are designed on a 2D map, the main feature are the walls, and areas are limited to a single height range (so a room over a room was not possible).

Thanks !