Promises are a fairly classic abstraction already, even in JS where they got formalized in 2012 with Promises/A+. Often misunderstood or under-used, they provide a solid fix to many of the pitfalls inherent to raw callbacks, and offer a wealth of extra features and goodness.

You can download all code samples for this part if you’d like to experiment on your own machine, along with all the videos for this part if you absolutely need to view them offline:
async-js-part-2-promises-code.zip 15.62 KB
async-js-part-2-promises-videos.zip 601.15 MB