Swift uses Automatic Reference Counting, usually called ARC, to manage memory for class instances.

A closure is a block of code that can be stored or passed around.

A data race can happen when multiple tasks read and write the same mutable data at the same time.

An enum represents a value from a fixed group of choices.

Some functions can fail. Swift makes failure visible with throwing functions.

Generics let code work with many types without losing type safety.

Protocols can be used in two important ways: opaque types and existential types.

An extension adds functionality to an existing type.

SwiftUI animations usually start with state.

A binding creates a two-way connection to data owned somewhere else.