In computer interface design, a ribbon is a graphical control element in the form of a set of toolbars placed on several tabs. The typical structure of a ribbon includes large, tabbed toolbars, filled with graphical buttons and other graphical control elements, grouped by functionality. Such ribbons use tabs to expose different sets of controls, eliminating the need for numerous parallel toolbars. Contextual tabs are tabs that appear only when the user needs them. For instance, in a word processor, an image-related tab may appear when the user selects an image in a document, allowing the user to interact with that image.

Use of the term "ribbon" dates back to the 1980s and was originally used as a synonym for plain toolbar. ^{[citation needed]} However, in 2007, Microsoft used the term to refer to its own implementation of tabbed toolbars encompassing a conglomerate of controls for Microsoft Office 2007, which Microsoft calls "The Fluent UI". Although Microsoft popularized the term with a new meaning, similar tabbed layouts of controls existed in prior software from other vendors, including 3D Studio Max R3 and later, Adobe Dreamweaver, Borland Delphi, Sausage Software HotDog, and Macromedia HomeSite.

Use of a ribbon interface dates from the early 1990s in productivity software such as Microsoft Word and WordStar as an alternative term for toolbar: It was defined as a portion of a graphical user interface consisting of a horizontal row of graphical control elements (e.g., including buttons of various sizes and drop-down lists containing icons), typically user-configurable.

A toolbar interface, called the "ribbon", has been a feature of Word from the early MS-DOS-based Word 5.5 (ca. 1990) and the first Windows-based versions (activated by the "View |Ribbon" menu option), for which early advertising referred to the use of "the Ribbon to replace an endless string of commands to let you format characters by eye instead of memory".

With the release of Microsoft Office 2007 came the "Fluent User Interface" or "Fluent UI", which replaced menu bars and customizable toolbars with a single "Office menu", a miniature toolbar known as "quick-access toolbar" and what came to be known as the ribbon: multiple tabs, each holding a toolbar bearing buttons and occasionally other controls. Toolbar controls have assorted sizes and are classified in visually distinguishable groups. The new design was intended to alleviate the problem of users not finding or knowing of the existence of available features in the Office suite. The name "ribbon" was later purported to have originated from an early design idea by which commands were placed on a long pane that could be rolled like a medieval scroll; the name was retained after the scrolling mechanism was replaced by tabs.

Microsoft applications implementing ribbons each have a different set of tabs which house user controls for that application. Within each tab, various related controls may be grouped together. Double-clicking the active tab or clicking the "Minimize" button hides the command panel, leaving only the tabs visible. Repeating this action reveals the pane. The ribbon consolidates the functionality formerly found in menus, toolbars and occasionally task panes into one area.

In Microsoft Office 2007, only Word, Excel, Access and PowerPoint implemented ribbons. With the release of Microsoft Office 2010, however, ribbons were implemented in the rest of the Microsoft Office applications. Microsoft Office 2010 also added additional end-user customization support to its user interface.

Microsoft gradually implemented the Ribbon in some of its other software. The fourth wave of Windows Live Essentials applications, including Mail, Photo Gallery, Movie Maker and Writer, featured a ribbon. Since Windows 7, Paint and WordPad feature ribbons. On Windows 8, File Explorer followed suit. Ribbons also appeared in SQL Server Report Builder, Dynamics CRM 2011, Microsoft Mathematics v4.0, the desktop client for Microsoft Power BI, and some other programs that have since been retired.