These Swift playgrounds contain notes I took while reading the Language Guide in Apple's book "The Swift Programming Language (Swift 2 Prerelease)". The notes are not refined/edited at all; I only put them on Github for future reference.
SwiftBook.playground: The Basics, Basic Operators, Strings and Characters, Collection Types, Control Flow, Functions, Closures, Enumerations, Classes and Structures Swift
SwiftBook2.playground: Properties, Methods, Subscripts, Inheritance, Initialization
SwiftBook3.playground: Deinitialization, Automatic Reference Counting, Optional Chaining, Error Handling
SwiftBook4.playground: Type Casting, Nested Types, Extensions, Protocols, Generics, Access Control, Advanced Operators
Random.playground: Miscellaneous notes from other online sources (Apple Swift Blog, We ❤️ Swift, etc.)