Where is session data primarily stored?

Session data is primarily stored on the server. This design is important because it allows for better control over the data, maintaining security and ensuring that sensitive information is not exposed to the client. Server-side session storage means that when a user interacts with a web application, their data can be efficiently retrieved and manipulated without relying on the local environment or the browser's capabilities.

While some forms of data can be handled on the client side, such as cookies or local storage, these are not ideal for storing session data due to vulnerability to tampering and security concerns. Storing session data on the server allows for a more secure and robust management of user sessions, as it can be managed centrally and persist across different requests.

In this context, cloud storage can be considered as a server storage option when discussing scalable server solutions. Thus, while there are various places where data can be stored depending on the application design, in terms of best practices for session management, server-side storage is the most effective and secure method.