what is media queries?

A media query is an HTML/CSS feature that enables a Web page's content to change depending on the type of media being rendered, such as a computer screen, a phone, or a tablet.

CSS 3's media queries feature enables content rendering to adjust to various circumstances, like as screen resolution (e.g. mobile and desktop screen size). In June 2012, the W3C suggested standard was established, and it is a key technology for responsive web design (RWD).