OS X Yosemite has changed the way your Mac deals with your privacy. On the one hand, Apple has decided to enable hard drive encryption by default, despite the FBI requests not to.
On the other hand, every time you type in Spotlight, your location and local search terms are sent to Apple, and, according to developer Landon Fuller, other third parties like Microsoft.
Fuller’s created a website, Fix Mac OS X Yosemite, where he’s posted up a way to stop Yosemite from sending such private data out. He’s also been contributing to a developer project on GitHub to find out and fix other ways that OS X phones home.