Nowadays it is common that visits on your website consists of considerable amount of visitors from mobile devices. It is important to have website that is optimized for smaller displays to make it easier to browse for your users, and that is the main idea of publishing something for your customers.
Responsive Web Design makes your web page look good on all devices (desktops, tablets, and phones). I’m using world’s most popular front-end component library Bootstrap which make it easy to build responsive web design.
Standard width ranges for responsive web design