Normalize CSS: 

css is a small CSS file that provides cross-browser consistency in the default styling of HTML elements. That means, that if we look at the W3C standards of the styles applied by the browsers, and there is an in inconsistency in one of the browsers, the normalize.

Responsive CSS:

Responsive images are images that scale nicely to fit any browser size. When the CSS width property is set to a percentage value, an image will scale up and down when resizing the browser window.