The simplest form as a product of biscuits, found in ancient Egyptian tomb dated back in around 4000 BC, was the mixture of flour and water. Modern biscuit industry started in Britain as it managed to travel to countries around the world with its advanced navigation technology in the 19th century. Bread was unsuitable for storage during the long navigation for it contained high percentage of water (35%-40%), and therefore biscuit was invented as a sort of bread contained little water.
"The bread baked twice", origined from French "bis"(again) and "cuit"(bake), is the derivation of the word "biscuit". Biscuits, baked with flour and water or milk except barm, are very convenient and useful as storage food for travel, navigation and mountaineering, particularly for soldiers in time of war. Biscuit industry began the concept of the said storage food for emergency in the long navigation or during the war in its initial stage, then started to spread in handmade-type, and was popularized all over the world with the development of mechanism technology as well as manufacturing equipment and technique of biscuits after the industrial revolution. Species of biscuits include biscuit, cookie, cracker, etc.
参考资料:非机器翻译