Shimano 32- Hole Threaded Standard Bicycle Rear Hubs
About Shimano - "Shimano practices good local citizenship, pursues continued access to those areas that are enjoyed by outdoor enthusiasts, and is committed to minimizing our impact on the environment."
The hub drilling is the number of spoke holes. It must match your rim spoke count.
The cassette body type is the type of cassette and number of speeds the hub will accept.