Human communication also is often marked by context . That is, when we converse there are assumptions made about the subject of the conversation. If we are talking about culture in an Anthropology class, we would know from the context that we were talking about human society. If we are talking about culture in a Microbiology class, we probably would be talking about microbes. In either case, there would be no confusion about the subject being discussed because of the context in which the communication was taking place.
Computers are machines which recognize neither concepts nor context.
They have an IQ of zero, lack any sense of intuition and possess no magical properties. They simply retrieve sequences of characters. When told to search for a word or phrase, a computer retrieves all documents that contain that exact sequence of characters. Thus, computer retrieval is an extremely explicit process. The challenge is to translate concepts into a set of search terms that will retrieve documents on the desired topic.