Here's what I understand:

Street Tires - RE01R, RE050, Azenis, etc.

R-Comps - R888, NT-01, RA-1, etc.

Dot Approved Slicks (Also known as A-Comps?) - R1, C91, V710, Hoosier XXX, etc.

Full Race Slicks (Non-DOT approved) - Dunno what models??

Someone correct me if any of this is wrong? Also can someone fill in the blanks? I get so confused when talking about tire classifications...

 

"R-compounds" are tires like the Hoosier A6, Kumho Ecsta V710 and BFG g-force R1. Made from a compound that's all about grip, with very little concession to life, and only the minimal tread to qualify as DOT legal. These are not considered slicks. There are older DOT r-compound tires that have more tread pattern, like the Kumho VictoRacer V700 and PZero Corsa. I think SCCA demarks r-compound from street compount at 120 UTQG or something?

I have never heard of an "A-compound" tire.

Slicks are what you see ALMS cars and such race on.