The first thing to consider is the ratio of salt to sugar. A higher ratio of salt works best in rubs for beef, fish, and wild game, while those with more sugar are better suited for pork.
Salt―Refined, fine grained (included in Big Bob’s secret pork shoulder seasoning)
Kosher salt―Additive-free, coarse grained
Sea salt―From evaporated seawater;
usually very fine grained
Seasoned salt―Regular salt combined with flavoring ingredients (e.g., garlic salt, onion salt, celery salt)
White sugar―Highly refined cane or beet sugar; will scorch at hotter temperatures
Brown sugar―White sugar combined with molasses; adds color and flavor to barbecue