What gives red beers the red color?

Factual Questions
1

Another late-night at the Diner conversation (see thread on overdrying clothes):

In redder varieties of beers, what exactly is it that we are seeing as red? Is it a single isolatable element (element in the more general sense) of the beer? a combination of things that blend to produce the red color perhaps? something else?

2

The color of a brew mostly comes from the type of malts that are used. Often a caramel malt is used to get that color (and contribute to the flavor profile)

3

I THINK that it has to do with how long some of the ingredients (hops? barley?) are cooked (roasted?) but I could be wrong - I heard this on the brewery tour at Coors in the late 80’s, and the ‘samples’ (Killian’s!) at the end were copious indeed.

4

As a homebrewer, I’ve always used roasted barley to get that “red” effect. The roasted barley does not contain sugars, so it is for taste and color only. You also need to use a light colored malt, or the beer will be too dark to see the red.