© The Author(s), under exclusive license to APress Media, LLC, part of Springer Nature 2022
W. WangPro iPhone Development with SwiftUIhttps://doi.org/10.1007/978-1-4842-7827-7_5

5. Understanding Concurrency

Wallace Wang1  
San Diego, CA, USA

Most computer programs run instructions sequentially. In many cases, that’s fine, since computers can process instructions so rapidly that even calculating complex mathematical equations takes so little time that a computer program barely seems to slow down at all.

While the processors in today’s iPhone and iPad models rival the processors used in desktop and laptop PCs, there’s still a problem running instructions sequentially no matter how fast they can be processed. Suppose a program needs to retrieve data ...

Get Pro iPhone Development with SwiftUI: Design and Manage Top Quality Apps now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.