As we all know,The Compass ,Gunpowder ,Papermaking,and Printing are our Chinese great inventions.Our ancestors created them by their own mind and hand.These inventions not only have an effect on our daily life,but also contribute to the culture all aroud world.But which is the most useful and practical invention to us?Well,as far as I concerned,the paper that we use now was first invented in Han dynasty,at that time this invention did improve their hand writing.Just imagine how our life will be if we live without paper?so,in a word,I think the paper is the most useful invention.