Spotlight is a brilliant feature of OS X on the Apple mac, of course, and it is an excellent tool for finding files on the disk drive you cannot remember where you've put. We've all done it at some point - saved a file and the next day, week or month, we can't find where it is. Gremlins seem to get on your Mac while you are asleep and move files around so you can't find them the next day!
Although Spotlight is an essential tool for Mac users, you might find that it constantly runs in the background and wastes time and processing power indexing stuff you don't want or need indexing. An example of this is an external hard disk drive that contains files you won't need to search, or a USB flash memory drive that you frequently use. Plug these in and Spotlight indexes them when it is not really unncessary. If there are drives you don't need indexing, you should set them up as exclusions to save time and processing power.
Click the Apple menu in the top-left corner of the screen and select System Preferences from the menu that drops down. Click Spotlight in the Personal section and select the Privacy tab. You'll see an empty list of excluded items. You can either click the Plus button and select the disks or folders you want to exclude, or drag them from a Finder window and drop them on the list. That's it, they won't be indexed by Spotlight.
As the name of the tab suggests, this feature is also about privacy and there may be folders that contain files you don't want to turn up in Spotlight searches. Just click the plus button and add those folders to the exclusions list.
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