It is difficult to imagine what life would be like without memory. The meaning of thousands of everyday perceptions (感觉，知觉), the bases for the decision we make, and the roots of our habits and skills are to be found in our past experiences, which are brought into the present by memory. (76) Memory can be defined as the capacity to keep information available for later use. It includes not only “remembering” things like arithmetic or historical facts, but also involves any change in the way an animal typically behaves. (77) Memory is involved when a rat gave up eating grain because he has smelled something wrong in the grain pile. Memory is also involved when a six-year-old child learns to swing a baseball bat. (78) Memory exists not only in humans and animals but also in some physical objects and machines. Computers, for example, contain devices for storing data for later use. It is interesting to compare the memory-storage capacity of a computer with that of a human being. The instant-access memory of a large computer may hold up to 100,000 “words” – ready for instant use. An average U.S. ager probably recognizes the meaning of about 100,000 words of English. (79) However, this is only a very small part of the total amount of information which the ager has stored. Consider, for example, the number of faces and places that the ager can recognize on sight. (80) The use of words is the basis of the advanced problem-solving intelce of human beings. A large part of a person’s memory is in terms of words and combination of words. 76. 77. 78. 79. 80. However, this is only a very small part of the total amount of information which the ager has stored.