Site optimization

I recently read an article about site optimization. It didn't go into much detail, but it made me very curious. What is site optimization? Is it a sister to search optimization? I'm going to have to add that to my list of research topics. I try and read whatever I can get my hands on to supplement my education in ebusiness.  I'll do some digging and report back on my findings about site optimization. Perhaps it's an entirely different direction for me to consider.