A browser user interface (or BUI) is a method of interacting with an application, typically hosted on a remote device, via controls presented within a
web browser
A web browser is application software for accessing websites. When a user requests a web page from a particular website, the browser retrieves its files from a web server and then displays the page on the user's screen. Browsers are used on ...
. This is an alternative to providing controls via a separate application with a dedicated
graphical user interface
The GUI ( "UI" by itself is still usually pronounced . or ), graphical user interface, is a form of user interface that allows User (computing), users to Human–computer interaction, interact with electronic devices through graphical icon (comp ...
(GUI) or
command-line interface (CLI).
BUIs have become common for devices that have their own
embedded microprocessor
A microprocessor is a computer processor where the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. The microprocessor contains the arithmetic, logic, and control circ ...
and network interface, such as a
printer or
network router
A router is a networking device that forwards data packets between computer networks. Routers perform the traffic directing functions between networks and on the global Internet. Data sent through a network, such as a web page or email, is ...
.

Since it is now expected that most owners or managers of such devices have access to a computer with a web browser, it is more convenient for both the device manufacturer and the device owner to use a BUI rather than shipping a separate GUI application, which would require installation and updates on one or more computers. A web browser provides a much richer interface environment than a command-line interface.
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User interfaces