NCache lets you cache data closer to your application in the middle-tier so you can reduce expensive trips to the database. This in turns significantly speeds up your application. It also makes it more scalable because the load on your database is reduced allowing it to handle a larger number of clients without any hardware upgrades.
However, when you cache data, you're actually creating a copy of it outside of your database. This introduces the risk that data in your database would be modified but your cached copy would remain unchanged and become stale. The good news is that this situation occurs only when you have multiple applications modifying the same data in the database and when not all of them are updating the cache.
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