To make things more confusing, this behavior is only designed into METRO apps, and not Desktop apps (with SOME exceptions, like, say, Google Chrome, which have the Metro-style touch-text-box,-get-On-Screen-Keyboard-popup-automatically enabled as a 'feature' you can't turn off)

Windows 8.1 was designed with a heavy emphasis on touch screens ('traditionally' on tablets.) If a touch screen is present, Windows 8.1 assumes that a keyboard is not, so any time you poke your finger onto the screen within a text box, a keyboard pops in (because it thinks you don't have one available, so you'll obviously need a way to type in yonder text box, dig?) However, if you have a convertible machine like your Yoga, which has both a touch screen and a physical keyboard, Windows doesn't know that It just thinks you have a touch screen ONLY, with no keyboard, so it keeps pushing that annoyingly redundant On-Screen Keyboard up in yo' grill even though you've already got a perfectly functioning 'IRL' keyboard right in front of you. What follows is an explanation and a solution.

On screen keyboard windows 8