Session items are specific to a particular user and span pages.
Session(yourKey) = someObject
Application items are shared by all users
Application(yourKey) = someObject
Cache items are also shared by all users but give you flexibility in expiring each item.
If you using VB.NET and are looking for an Application scoped variable, then you should use a public variable declared in a Module outside of any Class. According to the MS docs, this is faster than using an Application item.
When using application scoped variables, always stay conscious of threading issues.
i.e. two users updating the var at the same time...
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