In macOS, Apple combined both functions into a single strip of icons called the Dock.Īpple’s thinking goes like this: Why must you know whether a program is already running? That’s the computer’s problem, not yours. The other kept track of which programs were open at the moment for easy switching, like the taskbar (Windows) or the Application menu (Mac OS 9). One listed unopened programs until you needed them, like the Start menu (Windows) or the Launcher (Mac OS 9). For years, most operating systems maintained two lists of programs.