Last month, MIT OpenCourseWare served its 9 billionth web hit since we launched in 2003, a humblingly large number for us to surpass.

For those who don’t live and breathe web metrics, a web hit is basically a file of any type delivered by our servers. A web page might generate ten different hits—one for the underlying HTML file, one for a logo image, one for a title image, etc.

On the other hand, the PDFs that contain much of our content also count as a single hit each, so this measure can also represent a substantial amount of information, especially when some of our PDFs contain dozens of pages.

All of which is a long-winded way of saying that web hits don’t equal visits, which is how they are often presented, but they do provide a gross measure of activity on a site, and are usually the largest raw number in a set of web metrics.
Some of the other numbers we’ve run up are also quite remarkable. Since 2003, and as of March 31, 2013:

  • 807,691,478 page views
  • 124,433,178 visits
  • 76,960,450 unique visitors
  • 43,385,887 YouTube Views
  • 41,461,245 iTunesU downloads

Numbers like these were simply unimaginable when we started OCW, and we are thrilled to have been able to reach so many with the great materials created here at MIT by our generous faculty.