MenuBar

A menubar, or menu bar, is a horizontal row of commands typically located at the top of an application window or at the top of the screen on some operating systems. It provides access to the application's menus and commands, organized into top-level menus such as File, Edit, View, and Help.

Each top-level menu contains a list of menu items, which may execute commands, open submenus, or separate groups with dividers. Some items are checkable, radio, or have keyboard shortcuts (accelerators) that activate commands without opening the menu.

Platform variations: In macOS, the menu bar is a global bar at the top of the screen rather than confined to a window, with the application name on the left and system-wide items on the right; in Windows and most Linux desktops, menu bars appear within each application window or as part of the window's chrome.

Design and usability: The menubar provides discoverability and keyboard efficiency but should be concise and logically organized. On mobile platforms, menubar equivalents are often replaced by a hamburger menu or bottom navigation. Accessibility considerations include keyboard navigation, proper focus order, and screen-reader labels.

In software development, menu bars are implemented via platform or toolkit components such as Cocoa's NSMenu on macOS, Win32 HMENU on Windows, GTK or Qt for cross-platform applications. Developers may also place actions in context menus or toolbars alongside the menubar.