Within next 2 or 3 years, it would be suicidal for any website design to focus purely on customers who access or open them from desktop computers. The world is moving to an era where all websites must be designed in a manner that allows for easy access from desktop computers and all other devices, including mobile phones and tablets. Web developers are ahead of the rest of the world in this regard many years ago. They focused on encouraging their clients to build websites that were mobile friendly. A mobile friendly site carries less content or information, has very easy navigation and larger buttons. However, as popular as mobile sites might have been, they are on the verge of replacing with responsive sites.
Google, which is the biggest search engine in the world, believes that all websites should be accessible through all devices without having to change the URL. In fact, according to Google, the delivery of the same HTML to all gadgets through nothing else apart from CSS is now a major requirement. What this means is that opening the same website on multiple gadgets such as laptops, desktop computers, tablets, iPads, Smartphone devices and ordinary cell phones is now a requirement. A responsive design or website is accessible to all gadgets or devices. A mobile site might be accessible to cell phones alone. A mobile site is a compressed or much lighter version of the website accessible through desktops.
When looking at a mobile website, the visitor shall see a few pages compared to what he can access when opening the desktop version. However, the mobile site has a link that directs visitors to the main website that contains more information. Trying to access the mobile site through a Smartphone allows the site to recognize the device, thus directing the visitor to the appropriate mobile version of the site. The mobile website is less costly for businesses. The fact that it contains few images, if any, less content and is a much lighter version makes it perfect for businesses that would love such sites without paying over the odds. Mobile sites are best short-term solutions.
On the other hand, the responsive sites has the sort of features that makes it easier for any visitor to access it through smartphones, tablets and desktops. The beauty of responsive websites is that there is no need to create a separate version for smartphone devices. The main website contains features that allow it to adjust, thus fitting into the screen of the smartphone, desktop or tablet. Regardless of the type of device the visitor is using to access the website, he does not have to worry, as it shall fit his screen perfectly. With this explanation, it is much easier to see why responsive websites appear to be edging mobile sites in terms of popularity or increased usage.
While responsive websites are perfect for SEO-based websites, the same cannot be said of mobile sites. On the other hand, when building a mobile friendly website, it is possible to fill it with responsive design. What this means is that visitors can open and access a single site through a plethora of devices. A business that runs an ecommerce site ends up saving a load of money, as it does not need to build more than one version of a single website. The responsive design on its mobile friendly website ensures easy accessibility by all visitors regardless of the device they use.