I had absolutely no idea what these meant before but just doing a little research in just under 10 minutes i found out that V6 means there are 6 cylinders in a V shape configuration, V4 means more MPG but less power, V6 is mid range, and V8 means more power but poor MPG. reason for the V shape is it gives more power from same amount of cylinders(as in just having a standard cylinder).
24V means there are 24 valves, the more valves, the more air can get into the engine the faster the car will accelerate.
I hope the advice above is correct and i have translated it correctly.
I also hope this helps anyone out there.