Means (1994) describes the four functions of technology used for learning:
Technology is used as a tutor when it does the teaching directly, typically in a lecture-like or workbook-like manner. Tutorial uses include expository learning, in which the technological system provides information; demonstration, in which the system displays a phenomenon or procedure; and practice, in which the system requires the student to solve problems, answer questions, or execute a procedure.
In contrast, technology is used to explore when it allows students to move through information or obtain demonstrations upon request. Through the discovery or guided discovery that accompanies an exploration, the student can learn facts, concepts, procedures, and strategies as he or she interacts with the system. A microworld simulation is an example of using technology to explore something.
Technologies applied as tools provide students with the same kinds of tools generally found in the workplace or the home. These technologies, unlike technologies that tutor and explore, are not designed explicitly for school use but can be put to educational purposes. Examples include word processing and spreadsheet software, video cameras, and video editing equipment.
Finally, use of technology to communicate encompasses programs and devices that allow students and teachers to send and receive messages and other information through networks or other technologies." (pp. 9-10)