Page speed

A lot of effort goes into making onCourse really fast, even when displaying faceted search results from thousands of courses. We use separate SSL/TLS load balancers to remove encryption load from the application servers, we cache database requests and page rendering, and use Apache Solr as a high speed search cache. We also offload large image serving to a third party AWS S3 storage, again increasing the speed with which your site displays.

The end result of all this is that search engines give your site bonus points for being fast. Which is good.