Shared by Ian Lewis
Nice explanation of synchronous/asynchronous programming.

Asynchronous programming is superior both in memory usage and in overall throughput when compared to synchronous programming . We've known this fact for years. If we look at Django or Ruby on Rails, arguably the two most promising new web application frameworks to emerge in the past few years, both of them are written in such a way that synchronous programming is assumed. Why is it that even in 2010 we're still writing programs that rely on synchronous programming ?