http://www.techradar.com/news/the-old-android-menu-button-is-lurking-in-the-google-pixel-2s-interface

Are you an Android user who misses the old menu button – the one that used to be a defining feature of the operating system? You'll be happy to know it's still alive and kicking on the Google Pixel 2. 

However, it's hidden so well that it's taken a while for anyone to find it. It's the Luke Skywalker of user interface elements.