Grab a copy of "The C Programming Language", Second Edition
by Brian W. Kernighan and Dennis M. Ritchie.
It is one of the clearest introduction, also one of the shortest.. You won't learn much in 24 hours or even 21 days, but you'll learn it in a couple of months...
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lisp hacker

running: FreeBSD 5.4 - still learning

develop with: SBCL + emacs for lisp, Anjuta IDE +gcc for c, SPE for python..
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