Traditional fare. The biscuits store well, but they are so tasty, they don't last long before another batch needs to be baked.
Hardtack is essentially plain flour, salt and water. Plenty of carbs for energy and whatever protein and other nutrients that the flour might provide, but it is tasteless and doesn't have much in the way of fibre. ANZAC biscuits are tastier, and, depending on ingredients IMHO have a better palatability and nutrient profile than Hard Tack. Let Father John Fahey have the last word on Army (Hardtack) Biscuit... "...Father John Fahey, a Catholic padre serving on Gallipoli, was unimpressed with army biscuits. He wrote, "the man who invented the army biscuit was an unmitigated rascal. As an eatable there is little to choose between it and a seasoned jarrah* board..." * Jarrah is an Australian hardwood timber, often used in building construction around the time of WW1. ANZAC Biscuits were a welcome alternative to Army Biscuit.
Hardtack is to eatable; you just have to use a rifle butt to tenderize it first. Remember, this stuff is left over from the last war!