Foley's Fourth Level

The fourth level, the lexical level, includes understanding user's mechanisms when structuring their interaction with the computer. A user's interaction with a computer is structured by the person who developed the interface. If the interface does not allow the user to structure their interaction in a user friendly way, the system interaction may not be satisfactory. For example, when looking for information, people often ask questions of other people. Many Web search engines do not allow the user to ask the computer a question in natural human language or conversation style. A classic site that does allow questions is the Ask Jeeves site.