CloudReady is an operating system that allows old computers to run quickly by booting from the cloud. It can be installed using a USB drive and stores user data in the cloud. The document provides instructions for installing CloudReady, including downloading files, using a USB creator, and selecting install options. Dual booting with Windows requires at least 32GB of free space and disabling features like fast startup and encryption. The overall purpose is to breathe new life into old devices by making them run faster with a cloud-based OS.