Here's a popular graphic design related question that was closed then deleted from Stackoverflow:
It's clearly offtopic for stackoverflow, but the top answer is very good quality and on topic for the graphic design stack exchange site (http://graphicdesign.stackexchange.com).
That was a very useful question to link to for newbies struggling to grasp the basics, and there are a lot of links to that question that have now gone dead. It'd be great if it could be migrated to the design site.
(there are also a lot of poor quality answers, but the GD.SE mods can probably clean those up)