For decades, a model called Fitt's Law has governed click-based interactions with computers. Among other things, it came to the common-sense conclusion that large icons were better than small ones, corners and edges were easy to click on, and that menus on the top of the screen (as on OS X) were easier to find than ones on the tops of windows. John Pavlus of Technology Review, though, has talked to user interaction expert Francisco Inchauste about whether the rise of touchscreen gestures have created a system to which Fitt's Law is no longer relevant. Inchauste says that while Fitt's Law still applies, following it requires rethinking what a "target" means once it's no longer a fixed point on a screen.