Explore the concept of type erasure in Swift programming through this 22-minute conference talk from try! Swift Tokyo 2016. Delve into the intricacies of types, learn the meaning and necessity of type erasure, and understand its practical applications. Follow along as speaker Gwendolyn Weston, a developer at PlanGrid, guides you through concrete and abstract types, instantiation of abstract types, and the challenges that necessitate type erasure. Discover how to handle covariance in Swift, examine the downsides of type erasure, and gain insights on preserving type information. Conclude with a comprehensive recap and practical advice on mastering type usage in Swift development.