Hello, I have a late 2013 Retina Macbook Pro running Yosemite, with 8 Gigabytes of RAM. I noticed that on the Activity Monitor it shows that I have over 1 Gig of "swap used"! In the screenshot it says 974 megabytes, which is still bad. I've heard that it's okay for your memory usage to be high as long as the memory pressure graphic is green, but I've also heard that swap shouldn't be used, especially not 1 Gig of Swap. I'm not running any high intensity programs, only Safari, Spotify, iMessage, Mail, iTunes, Chrome, and things of that sort. Why would it be so high? High swap used is a bad thing, because it uses the SSD and shortens its lifetime. I don't even know why I would be using it, as I'm not running anything very intense. What can I do? What should I do? Should I re-install Yosemite from scratch? Does anyone know what app could be making this happen in the background?