[OSM-talk] Explanation of crowd sourcing?

[Dave F.]

Hi

I wanted to send a link to people who'd never heard of OSM that explains 
the basics of what it is & entails, but I couldn't find a page with a 
clear, simple explanation of what crowd sourcing is & that they can 
contribute .

Even the beginners' guide seems to jump the first step by assuming the 
beginner knows they can contribute:
http://wiki.openstreetmap.org/wiki/Beginners%27_guide.

Am I going blind & there is such a page?

Cheers
Dave F.