Google Chrome

Chrome's defining move was collapsing the address bar and the search box into a single field, the omnibox, and the entire industry followed. Type anything and it races between URL completion, search suggestions, and history, ranking them in a dropdown that updates with each keystroke. The chrome itself is deliberately thin: tabs sit at the very top edge, the toolbar carries almost nothing, and the page gets the room. That restraint is both the strength and the tell. Tab overflow is where it falls down, tabs shrink to slivers until favicons vanish and titles turn unreadable, and Chrome offers little native rescue beyond scrolling. It set the baseline expectation for how a browser should feel, then largely coasted on it.