What was significant about the Joint-stock company?

Since this is not my area of expertise, I searched Google under the key words "joint stock company" to get these possible sources:

http://en.wikipedia.org/wiki/Joint_stock_company
http://www.investorwords.com/2668/Joint_Stock_Company.html
http://www.investopedia.com/terms/j/jointstockcompany.asp
http://www.answers.com/topic/joint-stock-company

I hope this helps. Thanks for asking.