Your favorite assistant finally made its way to the Mac, starting with the macOS Sierra software update.
If you have used Siri on your iPhone or iPad before, then you'll probably feel right at home with the assistant on your Mac since it works in a similar way. However, unlike your iPhone, you don't have the ability to invoke Siri on your Mac by saying "Hey, Siri." Instead, you will have to click on the Siri icon in the Menu Bar, or in the Dock.
Another way to invoke Siri is by using a keyboard shortcut. Admittedly, this is my preferred way of activating the assistant as it feels faster and more efficient than reaching for the mouse or trackpad and clicking on the Siri icon.