saivann/bitcoin.org — pull request #16 by saivann (2014-03-21 17:22:13+00:00)
Title: Block chain introduction: Use a concise summary of the system and the subsection's content

As suggested previously, this introduction text could be used as a short summary for the subsection's content. We could drop details (like the 10 minutes block time) that are later mentionned and explained.