A collection of pre-written code and resources tailored for the Apple operating system that powers iPhones and iPads. These resources are designed to simplify the development process for applications. A common example is a set of user interface elements, such as buttons or text fields, which developers can readily incorporate into their applications instead of building them from scratch.
The utility of these collections lies in their ability to accelerate application creation, reduce development costs, and ensure a degree of consistency across different applications. Historically, these resources have evolved alongside the operating system itself, reflecting changes in design paradigms and technological capabilities. Their presence allows developers to focus on application-specific logic and features, rather than reinventing commonly used components.