1. The document discusses Swift Package Manager (SwiftPM), a new package manager for Swift packages and modules introduced in Xcode 8 and Swift 3. 2. SwiftPM allows defining packages and dependencies through a Package.swift file and building and linking packages through the swift build and swift run commands. 3. The author provides an example of initializing a package with SwiftPM, adding a dependency, building and running the package to summarize how SwiftPM works at a high level.