7. Storing and Retrieving Data

All computer applications require some sort of data with which to work as they execute. This is true of even the simplest applications. The data processed by an application may be embedded within it. Data may also be randomly generated or collected from the user as the application executes. In order to work with and manipulate data, programmers need the ability to store, retrieve, and modify data when an application runs. Within Scratch applications, data is managed using variables. The goal of this chapter is to teach you everything you need to know to begin developing Scratch applications that can collect, store, and process application data.

The major topics covered in this chapter include:

• How to create local and global variables

• How to use variables as a means of storing and retrieving data

• How to delete variables that are no longer needed

• How to view data stored in local variables belonging to other sprites