Drag racing classes?

What class do you guys run your cars in? I have been trying to find a site all day today that has a run down of the different classes and a basic summary of what each class consists of but I have yet to find anything. Figured I would ask you guys for some help.

What are the most common classes that the muscle car guys are running? And can you give me a basic rundown of what the class is?

Sorry if I am not being very clear :angry7: