Audi twelve valve and 30 valve?

what is the difference between these on the audi a4 2.8?

the twelve valve engine has two valves per cylinder, that's one intake and one exhaust so two valves total per cylinder times six cylinders equals twelve valves. The 30 valve engine has five valves per cylinder, that's three intake and two exhaust per cylinder so five valves total per cylinder times six cylinders equals 30 valves. Why do you want to have more valves per cylinder you ask?? So that the engine can breathe better and perform better after all an engine is simply a big air pump. Why could you want less valves?? Cheaper costs and less complex actuation of the valves. If you take a circle cylinder form that's say four inches in diameter and you place five smaller circles valve form so that they all take up as much room as possible in that four inch diameter circle versus putting only two big circles in that same four inch diameter circle that take up as much room as possible you'll realize that the five smaller circles will fill up more of the cirle than the two bigger circles. That lets more air and fuel to enter the cylinder hence better performance.