A radio button or option button is a graphical control element that allows the user to choose only one of a predefined set of mutually exclusive options. The singular property of a radio button makes it distinct from

checkbox A checkbox (check box, tickbox, tick box) is a graphical widget that allows the user to make a binary choice, i.e. a choice between one of two possible mutually exclusive options. For example, the user may have to answer 'yes' (checked) or 'n ...

es, where the user can select and unselect any number of items. Radio buttons are arranged in groups of two or more and displayed on screen as, for example, a list of circular holes that can contain white space (for unselected) or a dot (for selected). Each radio button is normally accompanied by a label describing the choice that the radio button represents. The choices are mutually exclusive; when the user selects a radio button, any previously selected radio button in the same group becomes deselected (making it so only one can be selected). Selecting a radio button is done by clicking the mouse on (or touching the screen over) the button, or the caption, or by using a keyboard shortcut.

Etymology

Radio buttons are named after the physical buttons that were used on old

radio Radio is the technology of communicating using radio waves. Radio waves are electromagnetic waves of frequency between 3 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmitter connec ...

s to select preset stations. When one of the buttons is pressed, the other buttons pop out while leaving the pressed one pushed in.

HTML

web forms ASP.NET is a server-side scripting, server-side web-application framework designed for web development to produce dynamic web pages. It was developed by Microsoft to allow programmers to build dynamic web sites, web application, applications a ...

, the

HTML element An HTML element is a type of HTML (HyperText Markup Language) document component, one of several types of HTML nodes (there are also text nodes, comment nodes and others). The first used version of HTML was written by Tim Berners-Lee in 199 ...

is used to display a radio button. Example: A group of attributes is defined by name. In one group, only one radio button can be chosen.

Unicode

Version 6 of the

Unicode Unicode or ''The Unicode Standard'' or TUS is a character encoding standard maintained by the Unicode Consortium designed to support the use of text in all of the world's writing systems that can be digitized. Version 16.0 defines 154,998 Char ...

standard includes a character designated to represent a radio button, (🔘) at code point 128,280 (U+1F518), found in th
Miscellaneous Symbols and Pictographs
section. Similar characters are the

mathematical operator Mathematics is a field of study that discovers and organizes methods, theories and theorems that are developed and proved for the needs of empirical sciences and mathematics itself. There are many areas of mathematics, which include numb ...

as well as and . The font

Wingdings Wingdings is a series of dingbat typeface, fonts that render letters as a variety of symbols. They were originally developed in 1990 by Microsoft by combining glyphs from Lucida (font), Lucida Icons, Arrows, and Stars licensed from Charles Bige ...

2 contains at position 153 and 158

glyph A glyph ( ) is any kind of purposeful mark. In typography, a glyph is "the specific shape, design, or representation of a character". It is a particular graphical representation, in a particular typeface, of an element of written language. A ...

s that look like radio buttons.

References

External links

*: the HTML 2.0 specification, which defined radio buttons on the web.
W3 HTML 4.01 Specification
*Usage of radio buttons i

* {{Graphical control elements Graphical control elements

Etymology

HTML

Unicode

See also

References

External links