Finalize

• Used to free unmanaged resources like files, database connections, COM etc. held by an object before that object is destroyed.
• Internally, it is called by Garbage Collector and cannot be called by user code.
• It belongs to Object class.
• There is performance costs associated with Finalize method.

Dispose

• It is used to free unmanaged resources like files, database connections, COM etc. at any time.
• Explicitly, it is called by user code and the class implementing dispose method must implement IDisposable interface.
• It belongs to IDisposable interface.
• There is no performance costs associated with Dispose method.