[plt-scheme] Newbie question about Lisp

I have question about Lisp (Common Lisp, not Scheme).

Does anyone object to me asking here?  If so, can someone recommend a
better list.

I looked into comp.lang.lisp, but it appeared to have a lot of
traffic, and not many newcomers.

The questions is :

Why the "." in evaluating (cons 1 2)

returns (1 . 2)

But (list 1 2)
returns (1 2)

-- 
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Greg Akins
http://www.pghcodingdojo.org
http://www.insomnia-consulting.org/monologue