Why Wikipedia?

Wikipedia is a unique, previously nonexistent opportunity to collect in one resource a large percentage of the knowledge accumulated by all mankind and easily share it, again, with all mankind, while overcoming language and cultural barriers. 

It seems to me that every culture that wants to keep its language alive in the twenty-first century will need something like wikipedia.org So an easily accessible freely usable source of good quality information is vital. But sitting back and hoping that someone else will create it for me doesn't seem like a sound strategy to me.
Wikipedia is essential to the dissemination of knowledge to large masses of people. Wikipedia is a good and necessary tool for the progress of society. 

It is now one of the cornerstones of the information space. Along with Google, Facebook, Vkontakte, YouTube, and so on. And it came about thanks to the billions of man-hours of millions of volunteers around the planet.