Responsive web design changes and adjust itself a per the screen size being used.
We all live in a world where customers can visit our websites using various devices and to best support and assist them, a responsive web design is a must. A site must work perfectly regardless of any devices or screen sizes. If the website is not mobile friendly and the customer cannot find easily what they are looking for by using their device, chances are high that they will go to another website. That in most the cases means, they will go to another Client which might means loss of business.
One website perfectly make responsive can very easily serve the Clients effectively and fast. A mobile friendly website will also rate you higher in terms of SEO. Google has also recommended this and have also envisioned this as a probable ranking feature in future. Internet traffic from the mobile devices is increasing day by day and our websites has to be great in terms of user friendliness.
Mobile friendliness also gives you scalability and gives you the best chance to support newer devices in the future.
Making responsive website eliminates the costs of making duplicate websites in future.