Saw this on TV Patrol. Sharing the video:
Per Wikibooks:
Graham crackers were originally conceived as a "health food" made from whole wheat (specifically, Graham flour), but have since entered the cuisine of the USA as a basic biscuit often made from highly refined flour with added sugar or honey.Graham crackers are often used as an easy source of whole wheat for a recipe, by crushing for use in baked foods. They are a bit similar to the UK's digestive biscuits and Australia's whole wheat biscuits, or "wheatens".