Saving file information is used in many aspects of game development. We use it to save high scores, game settings such as sound on/off, locking/unlocking levels, and so on. They're not necessary to have, but good to have if you'd like to have those features included in your applications.
In Corona SDK, applications are sandboxed, meaning that your files (application images, data, and preferences) are stored in a location that no other application can access. Your files will reside in an app-specific directory for documents, resources, or temporary files. This restriction is related to the files on your device, not when you are coding on your Mac or PC.
We'll be using BeebeGames Class, created by Jonathan Beebe. It provides many easy and useful functions to use for games. Some of the notable functions included incorporate a simple way of saving and loading data that we'll be able add into our game. More information on BeebeGames Class...