Media queries are those which allows the website to work on different types of devices having different viewport that is we the developers allow the website to work on different types having different types of screen size or according to the device display .The developers set different width for the website to displayed according to the screen of the device that is for mobile phones the developers give max width of 400px while for tabs the width is 700px and varies according to their viewport and for laptops max -width is 700-1000px while for large screen devices the width range is above 1300px.CSS layouts are design given to the website so that it appears visual appealing to the user.there are different types of css layouts simple,float,position,grid and flow.