Stems from the old I-formation. Behind the center you had your "quarter" back. Behind him was the "half" back. Behind or to his side was the "full" back (quarter, half, full, get it?). And finally you had the guy at the very back, the "tail" back.

Traditionally your tailback is your main ball carrier, your fullback is the lead blocker, and your halfback is a combo of the two. All three are considered RB's (as opposed to the "throwing" back, which is your QB).

Our offense is a little far removed from the traditional "I", but those terms persist to define what an RB can do and what's expected of him. Algie will be our primary RB, but his skills and style are closer to a traditional FB than TB. Nate Carter will be our #2 RB in the game, but his skills and style are closer to a traditional TB. At times they'll both be in the game, and that's when they'll gravitate to the more traditional roles, but it's not like we're about to line up in the power I at any point this season.