Grand Central Dispatch (GCD)

About This Course

Many times your apps need to run lengthy operations in the background, like downloading data, but you don't want these operations to interfere with your UI. Apple's GCD (long form: Grand Central Dispatch) framework allows you to create asynchronous apps for iOS, ensuring smooth a smooth user experience in situations like the one mentioned above.

Why Take This?

Almsot all Apps consume data from web services, and therefore must use background threads for these lengthy operations. Even though we provide a black box solution for concurrency in the iOS Networking with Swift course, it is important that you understand how concurrency works in iOS. This knowledge is vital to deliver Apps that won't be rejected from the App Store and also provide a great user experience. On top of that, GCD is a frequent topic in iOS job interviews.

Prerequisites and Requirements

To be successful in this course, you should be comfortable programming in Swift, and understand closures. You can learn these skills in our [Swift Syntax](https://www.udacity.com/courses/ud902) course. Familiarity with _The Hitchhiker's Guide to the Galaxy_ and _The Matrix_ are also recommended in order to understand the jokes in this course.