A couple of years ago mobile website overtook regular desktop websites in terms of their traffic and engagement This had been predicted to happen for several years prior So when it did happen  and in 2015 Google started rewarding responsively designed websites with better rankings in its search engine  the practice of designing and developing ‘responsively’ (so that the website ‘responds’ in format according to the screen its been viewed on) was already pretty well a part of any reputable web design agency’s toolkit