In 2002, when MIT decided to experiment with placing course contents on the Web for open access, the university's officials knew they were breaking new ground and had no idea how the effort would be received.

On Tuesday, school officials revealed plans to make available the university's entire 1,800-course curriculum by year's end. Currently, some 1.5 million online independent learners log on the MIT OpenCourseWare (OCW) site every month and more than 120 universities around the world have inaugurated their own sites for independent learners. MIT has more than 1,500 course curriculums available online to date.

"About 40% of the MIT alumni population uses the site," said Steve Carson, the OCW's external relations director, in an interview Tuesday. "Usually they take courses they didn't have time for while they were students here." The courses are free of charge and no course credit is granted.

Carson said MIT's teachers collect what they have created for their courses and make it available over the Web. Many online learners purchase text books for the courses they are monitoring and a recent MIT-Amazon link showed that about 2,000 text books were ordered by independent learners, demonstrating just how serious the learners are.

"Video and audio files are very popular," said Carson. "There are 21 courses with full video available." Typically, independent learners view videos with streaming media players and replay them on PCs, MP3s, or iPods.

The entire effort has altruistic overtones of intellectual philanthropy. MIT's Anne Margulies, executive director of the program, recently described the OCW program as knowledge "shared openly and freely. MIT is using the power of the Internet to give away all of the educational materials created here."