Fixed, Fluid, Adaptive, and Responsive

  •     Fixed websites have a set width and resizing the browser or viewing it on different devices won’t affect on the way the website looks.
  •     Fluid websites are built using percentages for widths. As a result, columns are relative to one another and the browser allowing it to scale up and down fluidly.
  •     Adaptive websites introduce media queries to target specific device sizes, like smaller monitors, tablets, and mobile.
  •     Responsive websites are built on a fluid grid and use media queries to control the design and its content as it scales down or up with the browser or device.

Reference :-
http://www.onextrapixel.com/2012/04/23/responsive-web-design-layouts-and-media-queries/