Originally Posted by jhns
1) It is what it says. Dual core is like two processors running at once and quad core is 4. That means a quad core can process 4 pieces of information at the same time while a dual core only does 2. So a 3.0 Ghz quad core processor will be almost twice as fast as a 3.0 Ghz dual core processor.
Actually, the bolded part is not quite true.
A quad core processor is only ~25% faster than a dual core processor.