Discoverability - If user can't find it, it does not exist. Signifiers - Calling for action (Click me, edit profile picture, button, arrow etc) showing possible actions Feedback - Showing that button is clicked, page is loading... giving user feedback that it is working Conceptual models and mental models - top Navigation bar, sitemap at bottom Mappings - How knobs, thermometers work Constraints Consistency, standards, Heuristics Pattern and Learnability Visual Hierarchy and emphasis - size, proximity, color, opacity, and actual tonal contrast between elements Fitts law - The time to acquire a target is a function of the distance to and size of the target. Gutenberg Diagram, Z- and F-Pattern Layouts Recognition Rather than Recall Aesthetic and Minimalist Design Error Prevention https://www.toptal.com/designers/interactive/interaction-design-principles Large buttons are easy to target. Taking advantage of Fitts' Law, one can also introduce const