The term "session" is a technical term describing information which is remembered by an application for a particular user. Sessions work in conjunction which other mechanisms - typically cookies and user identifiers - like this:
Information can be said to be "persistent" when it is remembered beyond the lifetime of a particular request to an application. Sessions, meanwhile, are effectively a special case of persistent information - data is addressed or accessed using each user's identity, and the information is partitioned in such a way that sessions cannot be shared between users.
Sessions | Persistent Information | |
---|---|---|
Access | Through user identity. | Through any relevant concept: users, documents, orders, products, locations - anything an application might want to remember. |
Partitioning | By user identity. Each user has its own private data store. | Arbitrary. Many data stores or data sources may be set up. The data may be shared across the entire application or there may be access controls in place. |
Access to persistent information in general can be done in a simple fashion by using repositories (see "DirectoryRepository - Simple Access to Files in a Directory") or, for example, by using database access libraries - see "Integrating with Other Systems" for more details.