What is the purpose of using variables in OutSystems?

Using variables in OutSystems serves the primary purpose of storing data temporarily during the execution of an application. This allows developers to hold values that can be manipulated and accessed throughout the lifecycle of a particular function or screen, facilitating dynamic and interactive user experiences.

In the context of application logic, variables enable the handling of user inputs, system generated data, and other temporary states that are needed while an application is running. For example, when users input information into a form, that data is typically stored in variables before any further processing, such as validation or submission to a database.

The other options describe different aspects of application development. While defining structures is relevant to the overall architecture of an application, it does not specifically relate to the function of variables. Additionally, establishing connections between the server and client involves network protocols and communication layers rather than in-memory data storage. Lastly, the creation of user profiles involves data management and persistence rather than the temporary data manipulation that variables facilitate.