Update April 10, 2015: Updated for Xcode 6.3 / Swift 1.2
Update note: This tutorial was updated for iOS 8 and Swift by Bjørn Ruud. Original post by Tutorial Team member Derek Selander.
Although Grand Central Dispatch (or GCD for short) has been around for a while, not everyone knows how to get the most out of it. This is understandable; concurrency is tricky, and GCD’s C-based API can seem like a set of pointy corners poking into the smooth world of Swift.
In this two-part series, you’ll learn the ins and outs of GCD. This first part will explain what GCD does and showcase several of the more basic GCD functions. In the second part, you’ll learn several of the more advanced functions GCD has to offer.