During recent centuries, humankind has invented lots of things , accompanied by or due to the rapid progress of science and technology, such as cars, planes, medicine to cure cancers and various equipment used in factories. These have brought dramatic changes to our daily lives. People may have different ideas when arguing about which is the most important one, but as for me, I should claim that computers outweigh all others in their importance to us. Should this invention not come into reality, it is extremely hard to imagine what today's world will be.