What is the CSS responsive layout?

The reason for this is that the mobile Internet is no longer a small, independent network, but is becoming an important part of the Internet, as more and more smart mobile devices are added to the Internet. The advent of Responsive network design (RWD/AWD) is designed to provide a better experience for mobile devices and to integrate various screen sizes and resolutions from the desktop to the phone, using technology to adapt the web to different resolutions from small to large (now to oversized) screens.
Note : Responsive web design = rwd,adaptive Web designs = AWD, below
RWD: Media query technology with CSS
Fluid layout (fluid grids)
Adaptive image/Video and other resource materials
(For small, medium and large screen to do some optimization, the purpose is to make any size of screen space can be fully utilized)
AWD: CSS Media Query Technology (designed for limited number of preset screen sizes)
Using Javascript to manipulate HTML content
Manipulate HTML content on the server side (for example, reduce content for mobile and provide more content to the desktop)
Design Ideas Mobile first (from the Start, RWD): Everything starts with the smallest screen of the mobile phone (like the IPhone 320px), determines the content, and then goes to the big-screen design. Different from the original web design, always starting from the desktop computer 1024px.