While the Chrome Browser has been noted to be a memory hog, it seems that Safari can become one also, as noted in this article. I did notice that the author seems not to shut off his computer very often, and hence close Safari. My opinion is that it would be a good idea to frequently close any browser, which seems to reduce the memory usage. And talking about browsers, if you have an interest, here is a current article comparing several different browsers. The author thinks that while Chrome is the overall best browser, it is also the biggest memory hog. Right now Chrome is my browser of choice.
Just to see what I think about it, and the impact on memory usage, I may try the Opera Browser for a while.