Node.js explained by Ryan Dahl
jsconf.eu
jsconf.eu
Just a warning to any viewers: I think it might be a bit out of date now. I don't think node has promises anymore and I think they also have blocking and non-blocking versions for most operations (meaning callbacks are optional).
Quick summary: Node.js is a program/api written in C that lets you write asynchronous servers in javascript. All IO is done through event loops and callbacks.
If you are interested in the efficiency/architecture of server programs then this is worth watching.
on one way, recognizing (and translating the subtitles to english) other languages would be more important because most people already know english...