Windows 10 has Cortana, iOS has Siri, Android has Google Now, but what about Mac owners who want to bark orders at their computers? By using the new features OS X El Capitan adds to the Dictation tool and the Spotlight search interface, you can get a close approximation of Siri on your iMac or MacBook — even if it isn't quite as good as the real thing.
First of all, you need to set up dictation inside El Capitan and configure a command phrase that's going to trigger listening mode. From System Preferences, choose Dictation & Speech and make sure the feature is switched on; you should also check the tick box for Enhanced Dictation.
Then go to the Accessibility menu in System Preferences, scroll down to the Dictation panel and configure your shortcut word or phrase — you could use "hey Siri" but it might cause complications if there's an iPhone within earshot. Then click on Dictation Commands and tick the box marked Enable advanced commands.
With that you're pretty much ready to go: Say your shortcut phrase then "launch Spotlight" to bring up the search bar, which of course understands natural phrases in El Capitan and is able to return more results from the web. You can search for weather forecasts, stocks, sports scores and more, much as you can using Siri on your mobile devices.
It's not quite the full Siri experience, but it will do until Apple decides to add the digital assistant to its Mac OS X software. In the meantime, you might want to familiarise yourself with the voice commands supported by the software, which you can find on the Dictation Commands dialog we brought up earlier from System Preferences.