Siri

Siri will likely prove to be the biggest productivity enhancement of all in Sierra. As well as forecasting the weather, giving you travel reports and telling you what’s playing on the radio, she understands queries such as “Show me the Excel files I worked on this week,” “Launch Word” and “Send a message to Bob.” Your interactions with Siri are shown in a floating window, so you can continue working in another app while she walks you through each stage of a multistep operation — such as sending a message — entirely by voice.

If you need images to use in a document, say, you can ask Siri to “Search the web for Golden Gate Bridge” and then drag results from her window onto the page. Notice the results pane has a ‘+’ in the corner; click this to add the results, or any other list such as recent Pages documents, to Notification Centre for re-use.

In Siri’s pane in System Preferences, you can choose another voice for her, change the mic you use to communicate with her and assign a different key combination to invoke her.