HTML5 is the latest evolution of the standard that defines HTML. The term represents two different concepts. It is a new version of the language HTML, with new elements, attributes, and behaviors, and a larger set of technologies that allows the building of more diverse and powerful Web sites and applications.

As a web user, you will benefit from HTML5 because it fixes the most glaring problems in HTML4. Web sites will have better web standards, which will result in more efficient content and improved performance. As HTML5 is adopted across the board, web pages should start to load faster, less bandwidth should be used, and battery life on mobile devices ought to last longer.

Plus, you won’t have to keep so many plugins like Flash and Java updated. I hate it when I constantly have to update so many addons and plugins across multiple browsers. And what happens when one of them is the wrong version? Sites stop working and frustration ensues.

Cascading Style Sheets (CSS) is a style sheet language used for describing the presentation of a document written in a markup language like HTML. CSS is a cornerstone technology of the World Wide Web.

CSS3 is the latest evolution of the Cascading Style Sheets language and aims at extending CSS2.1. It brings a lot of long-awaited novelties, like rounded corners, shadows, gradients, transitions or animations, as well as new layouts like multi-columns, flexible box or grid layouts.

Responsive web design (RWD) is an approach to web design that makes web pages render well on a variety of devices and window or screen sizes. Content, design and performance are necessary across all devices to ensure usability and satisfaction.

A site designed with RWD adapts the layout to the viewing environment by using fluid, proportion-based grids,flexible images, and CSS3 media queries.