Spotlight, Apple's search technology, has been available on Macs since Mac OS X 10.4, back in 2005. For many years it remained relatively stable, offering no new features. But with OS X Yosemite, Apple added a slew of new search results to Spotlight.
If you use Spotlight, you may only invoke it to search for, say, contacts or emails, or the occasional file. But Spotlight can search for much more: it can search the web, find information on Wikipedia, convert pounds to grams (or dollars), define words, and more.
It's a good time for a Spotlight refresher course, and in this and a couple of upcoming articles, I'll look at searching with Spotlight on OS X, covering the basics first and then explaining how to use Spotlight for power searching.
First steps with Spotlight
Searching with Spotlight is easy. To invoke the Spotlight search bar, just press Command-Space or click the magnifying glass icon at the right of your menubar. Type one or several words and Spotlight provides live updates showing you matches.
In the example above, I searched for spotlight and the top hit was the Spotlight preference pane in System Preferences. If I want to open that, I can just press Return. But I can also scroll down the list to see a Bing search, a song on iTunes, a nearby bar that Maps found, a Wikipedia entry, a dictionary definition, and some articles I've written about Spotlight that are stored in my archives. If I keep scrolling, there are plenty of other files on my Mac that contain the word "spotlight."
As you can already see, Spotlight can return lots of search results. How can you sort them to get the ones you want? You could start by going to the Spotlight preference pane by pressing Return after searching for spotlight. (Or launch System Preferences and click on the Spotlight icon.) The Search Results tab in this preference pane lets you choose which categories display in Spotlight searches and their order.
As you can see above, I've not checked all the categories: I've chosen to not show presentations or spreadsheets in my search results. Also, I've dragged the search results around a bit; I've put Documents near the top, followed by Applications. (The order of these categories will probably be different on your Mac.) To change the order of these categories, just drag them in the list to where you want.
Depending on the types of files you have on your Mac and what you want to get from your searches, choose the categories you use most and come back to this preference pane after a while to rearrange the categories in the best order for you.
What you can search for
What can you find with Spotlight? Start with something simple, like an application you use often. Type, for example, SAF to bring up Safari, and then press Return to launch it. (Naturally, if Applications isn't checked in the Spotlight preference pane, Safari won't appear.) Are you looking for a file with information about a client, but can't remember the name of the file? No problem. Spotlight looks at file names and also the contents of files. If you want to find documents talking about the Acme Corporation, just type the name and check the search results.
Remember that Spotlight only shows the top results in its window; if you want to see all matches, scroll down in the list and click Show All in Finder. You'll see a new Finder window with every single file that matches your search.
Spotlight not only indexes the contents of documents but it can also show them to you. Search for something, then use the arrow keys to select an item. The right-hand pane shows a preview and you can even scroll through it and click any links in it. (Tip: make the window a bit larger so you can see more in previews.)
You can play songs or videos using the preview pane. And if you search for a contact, you can hover over their email address and click a button to send an iMessage or an email, call them via phone or FaceTime, or visit their website (if you've entered one on their contact card).
Spotlight goes much further. In addition to documents on your Mac, it can also search the web (using Bing only, unfortunately), Wikipedia, and Apple's online stores (iTunes Store, App Store, iBooks Store). Type movie theater to find your local cinema, including its location in Maps.
And Spotlight can also provide information. You can use it to convert units; for example, type 100 kg to see the equivalent in pounds, ounces, and tons. Type 100 GBP to see the equivalent in US dollars, euros, yen, or Canadian dollars. Use Spotlight as a calculator: type, say, (6*8)/4 to see the result of this calculation. And define words: type a word you don't know, and look for the Definition category to see an entry from the Dictionary app.
Slim down Spotlight search results
If you're using Spotlight with the default settings, you may have too many categories, leading to a glut of results. I explained above how you can limit which categories display, but you may also want to remove certain folders. If you open the Spotlight pane of System Preferences, and click the Privacy tab, you'll be able to add folders--or disks--that you don't want indexed.
To do this, either drag a folder or disk to the window, or click the + button, select an item, and then click Choose.
Spotlight is a powerful tool, and it behoves you to tweak it to work better for you. Not everyone has the same types of files, so choose the categories that match your searches, and put them in the right order. There's a lot you can do with Spotlight, and in coming articles, I'll tell you much more.